Forces and energy

Transcription

Forces and energy

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Introduction to Physics Teacher Resource
Pack
The Physics TRP is intended to support teachers
preparing students for the Physics component of
OCR Co-ordinated Science A or OCR Chemistry. It
is supported by a CD-ROM where much of the
material in the Physics TRP is available in a form
that can easily be adapted to meet the needs of
individual or groups of students.
is finished. Self-assessment is provided at both
Foundation and Higher levels. Using this
Self-assessment may highlight weaknesses to the
student.
Summary sheets for KS3
The OCR specification splits up the content into
Teaching blocks. These Teaching blocks are not all
of equal length. The Time Allocation page gives an
estimation of how much time should be spent on
each Teaching block. It is an estimate made by the
people who wrote the OCR specification and
should be a useful guide to teachers.
In GCSE examinations, even at Foundation tier,
examiners cannot examine KS3 material. Teachers
must therefore move on as quickly as possible to
KS4. However, understanding of KS4 often requires
remembering what was done at KS3. At the start of
each Teaching block there is a Check-up for
students. This could be done by students on a piece
of paper and followed up by discussion or could be
done with the class on a discussion basis. If some,
or all students have weaknesses, they can be given
a Summary sheet.
Activities
Student Checklists
There are 25 Practical Activities suitable for
students. Most of them are intended to help you to
develop Sc1 skills in your students before
Assessment. Some of these activities can lead to
Sc1 assessments. There is one activity on
Projectiles where full marking criteria are given.
Providing they are used correctly they should assist
Centres in their Sc1 assessment.
The Student sheets expand the OCR specification
and simplify the language for students. Students
could be given a copy of the Student sheet at the
start of the Teaching block. They then tick off the
statements as they cover them in column A. When
they are confident that they can answers questions
on the statement they tick column B. This then
provides the basis for their revision planning, first
for the End-of-block test and then for the Terminal
examination. It is hoped that using these will help
students organise really good individual revision
plans.
The main features in the Physics TRP are.
Time allocation
From 2003, computer based activities can be used
in addition to the traditional activities. There is
one example of a suitable computer-based activity.
Several of the activities give ideas of how ICT can
be used in student Practical Activities. There are
also examples of activities that can involve
Literacy and ICT.
Help with Key skills
These Activities are all arranged in the order that
they appear in the textbook.
The Physics TRP gives advice for teachers on
where and how to collect evidence for Key skills.
There are tables that can be completed to keep a
record of Key skills opportunities.
Learning support
Scheme of Work
Although Heinemann/OCR textbooks are written
for a wide ability range, we are conscious that it is
important to tailor materials for lower ability
students. Topic help is intended to do this and, via
the CD-ROM, have the maximum flexibility. It is
based upon using the Key words identified in the
textbooks. Many candidates fail to understand
scientific terminology and use it incorrectly.
To assist schools in producing individualised
schemes of work based on OCR A, tables are given
which summarise activities provided in Physics
TRP and further activities that could be used.
Self-assessment (Quizzes)
The Heinemann/OCR textbooks and Homework
books provide a whole range of questions. OCR are
providing End-of-unit tests that can be used to
monitor the progress of students. Self-assessment is
non-threatening and students can use it themselves
when there is a suitable time, e.g. before taking an
End-of-block test or when a piece of practical work
Answers to questions
The Physics TRP includes answers to all of the
questions in Physics double and separate Physics
books. Teachers can use these to mark answers or
copy the relevant parts and give to students. This
can be useful if students have missed work because
of absence.
It is hoped that the material provided by the
Physics TRP both in paper form and on Physics
CD-ROM, will supplement material provided by
OCR, and give a level of support much greater than
has ever existed before.
© Heinemann Educational 2001
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Physics
Contents
Contents
Schemes of work
Introduction to Key skills
vi–x
xi–xvii
Time allocation
xviii
Activities (numbers relate to book spreads)
Teachers’ and Technicians’ notes
32–65
1.1
Resistors connected in series
1
1.3A
Current–voltage graph for a metallic
conductor
2
Current–voltage graph for the filament
of a light bulb
3
2.1
Balancing metre rules
4
2.2
How speed affects stopping distance
6
2.5
Friction
7
2.7
To investigate a factor which affects the
distance travelled by a projectile
8
2.9
Measuring reaction time
2.10A
Dropping steel ball bearings in oil
11
2.10B
Velocity–time graphs for falling balls
12
Self-assessment
2.11
What difference does a lid make?
13
TB1
Electric circuits
119
3.4
Reflection of light by a plane mirror
14
TB2
Forces and energy
123
3.5A
Refraction of light by a perspex block
15
TB3
Wave properties
127
1.3B
9
3.5B (and A2.1)
Topic Help
Introduction
66
TB1
Electric circuits
67
TB2
Forces and energy
70
TB3
Wave properties
80
TB4
Using waves
85
TB5
Radioactivity
92
TB6
The Earth and Universe
97
TB7
Using electricity
100
TB8
Electromagnetism
105
Answers
111–118
TB4
Using waves
131
How does the angle change?
16
TB5
Radioactivity
135
4.1
The visible spectrum
17
TB6
139
4.6–4.8
Where do the earthquakes happen?
18
TB7
Using electricity
143
5.2
Absorption of radioactivity: Teacher
demonstration
TB8
Electromagnetism
147
19
TBA1
Electronics and control
151
5.3
Simulation of radioactive decay
20
TBA2
Processing waves
153
7.3
Use of a van de Graaff generator to link
electric charge and current:
Teacher demonstration
21
TBA3
More about forces and energy
155
8.2
How fast does the motor go?
22
8.3
How does voltage depend on speed?
23
8.4
Electromagnetic induction
24
8.5
Transforming the voltage
25
8.6
Literacy activity
27
Summary sheets
TB1
Electric circuits
157
TB2
Forces and energy
158
TB3
Wave properties
160
TB4
Using waves
161
TB5
Radioactivity
162
TB6
163
A1.1–A1.3 or A1.4 for High Tier pupils
Logic Circuits using AND, OR and
NOT gates
28
TB7
Using electricity
164
A3.6
Measuring specific heat capacity
30
TB8
Electromagnetism
165
A3.7
Efficiency of a ramp
31
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Physics
Contents
Student checklists
TB1
Electric circuits
166
TB2
Forces and energy
167
TB3
Wave properties
169
TB4
Using waves
171
TB5
Radioactivity
173
TB6
174
TB7
Using electricity
175
TB8
Electromagnetism
177
TBA1
178
TBA2
Processing waves
179
TBA3
181
Answers to pupil book questions
183–238
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Pupil book spread
Activities in Physics TRP
Further work
E. Resistors connected in series.
E Using a variable resistor with lamp and/or motor
Physics
vi
Exp – Experiment; ICT – Activity suitable for assessing Sc1; Lit – Literacy Activity
Electric Circuits
1.1 Circuit components
1.2 Measuring resistance
E. Measure current and voltage in series and parallel
E. Measuring resistance
1.3 More about resistance
E. Current–voltage graph for a metallic conductor
E Current–voltage graph for the filament of a light
bulb
CD-ROMs to enable pupils to construct, test and alter electric circuits on screen are: Crocodile Clips
(www.crocodile-clips.com/education) and Edison (REM Ltd, Great Western House, Langport, Somerset,
TA10 9YU)
Forces and energy
2.1 Turning forces
E-Balancing metre rules
Calculations involving moments
2.2 Motion graphs
E. How speed affects stopping distance
E-Comparing the advantages and disadvantages of using a stopclock, ticker tape and light gates to calculate
average speed
How speed cameras work
2.3 Displacement and velocity
E. Use a datalogger to measure distance, displacement and speed (and to graph the results)
2.4 Acceleration
E Use a datalogger to measure acceleration
E use a datalogger to measure velocity–time graphs
2.5 Forces
E. Friction
2.6 Force and motion
E. Forces acting on objects in various situations and link to motion
CD-ROM Multimedia Motion- show and analyse different types of motion. Cambridge Science Media, 354
Mill Road, Cambridge CB1 3NN
2.7 Force and acceleration
Sc1- To investigate a factor which affects the distance E. Verify F = ma using ticker tape and light gates with a ticker timer
travelled by a projectile
2.8 Force and energy
E. Measuring personal power
E Measuring reaction time
2.10 How things fall
E. Dropping steel ball bearings in oil
2.11 Keeping warm
ICT–What difference does a lid make?
2.12 Energy efficiency
E. Efficiency of simple machines (ramp and pulley
systems)
Literacy – Discussion of the effects of increasing size of lorries on our roads
E. Velocity – time graphs for falling balls
E. Compare the conductivity of various materials
ICT – Internet research on U values for different materials
ICT – Internet research on combined heat and power systems
Wave properties
3.1 What are waves?
E. Looking at waves with slinky springs, tuning forks and musical instruments
Scheme of Work
2.9 On the road
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3.2 Wave characteristics
Further work
E. Examine waves in vibrating springs to show amplitude, frequency and wavelength
3.3 Water waves
E. Use ripple tank and curved waves at straight and curved barriers
3.4 Reflection of light and sound
E. Reflection of light by a plane mirror.
3.5 Refraction
E. Refraction of light by a perspex block
Physics
Pupil book spread
ICT – Research on acoustic baffles and sound absorption materials
ICT – How does the angle change?
3.6 Images
E. Image positioning by no-parallax for both reflection and refraction
E. Counting images in inclined mirrors
Making kaleidoscope
3.7 Diffraction
E. Use a ripple tank to demonstrate diffraction
Using waves
4.1 The electromagnetic spectrum
E. The visible spectrum and show ir beyond red with
ir detector.
E. Showing ir beyond red with ir detector
ICT – Internet research on Newton
4.2 Infrared and ultraviolet
4.3 Opposite ends
ICT – Research satellite dishes, e.g. www.goonhilly.bt.com
Location of mobile phone masts
4.4 Total internal reflection
E. Demonstration of use of optic fibres
ICT – Research endoscope images on Internet
4.5 Ultrasound
4.6 Seismic waves
ICT – Research on uses of ultrasonics on Internet
ICT – Where do the earthquakes happen? (Also 4.7
and 4.8)
E – Showing vibrations travel through the Earth
Interpreting traces of seismic waves
4.7 The structure of the Earth
4.8 Plate tectonics
ICT – Research on the Internet of the work of Wegener
Study of the effects of recent earthquakes
(Possible links with Geography department throughout)
5.1 What is radioactivity?
E. Demonstrate background radioactivity
Leaflets on radiation and its effects from Press and Information Officer, National Radiological Protection
Board, Chilton, Didcot, Oxon OX11 0RQ
SATIS (Science and Technology in Society) – published by ASE – 204 Using radioactivity, 1105 Radon in
homes
Sang, David 1997 Henri Becquerel and the Discovery of Radioactivity (ASE publications)
Research on Becquerel on the Internet
Ellis, P1999 100 years of Radium (ASE publications) – the work of Pierre and Marie Curie
5.2 Properties of radiation
E. Absorption of radioactivity: Teacher
demonstration
5.3 Radioactive decay
ICT – Simulation of radioactive decay
E. Demonstrate ionisation of air using spark counter Structure of film badge – also NRPB
vii
5.4 Using penetrative power of radioactivity
E. Demonstrate smoke alarm
5.5 Other uses of radioactivity
ICT – Research on Turin shroud, Iceman and radiocarbon dating
Scheme of Work
Radioactivity
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Further work
5.6 Using radioactivity safely
6.1 Our Solar System
Physics
viii
Pupil book spread
ICT – Internet research with NASA sites(www.nasa.gov)
CD-ROM – Astronomy, Anglia Multimedia, Rouen House, Rouen Road, Norwich, NR1 1RB
Posters, slides, videos, CD-ROMs available from Public Understanding of Science, Particle Physics and
Astronomy Research Council, Polaris House, North Star Avenue, Swindon, Wiltshire, SN2 1ZZ
6.2 The life cycle of stars
Slide set Stars and Galaxies II (available from Armagh Planetarium)
(www.armagh-planetarium.co.uk/index.htm)
Shows photographs of a star that blew up. Source of other useful materials
6.3 The evolution of the Universe
Using electricity
7.1 Electrostatic phenomena
E. Using polythene and perspex rods for electrostatics
7.2 Uses and problems of electrostatics
7.3 Charge and current
E. Use of a Van de Graaf generator to link electric
charge and current: Teacher demonstration
E. Demonstrate ping-pong ball between charged plates
7.4 Electricity in the home
E. Measure energy transferred by different appliances (using a.c. ammeter or power using a joulemeter)
7.5 Electrical safety
Resources available from local electricity company
7.6 Paying for electricity
Wattville is a CD-ROM available from Understanding Electricity. It looks at electricity consumption in the
home
Electromagnetism
8.1 Force on a wire in a magnetic field
E. Demonstration of ‘kicking wire’ experiment
Construction of a loudspeaker
8.2 Electric motors
ICT – How fast does the motor go?
E. Making a model motor
8.3 Electromagnetic induction
ICT – How does voltage depend on speed?
E. Demonstration of induced voltage (by moving a conductor in a magnetic field and by a magnet near a
fixed coil)
8.4 Generators and mutual induction
E. Electromagnetic induction
E. Use a CRO to observe output from a dynamo
.
E. Use a datalogger to graph output from a dynamo
E. Show that a motor can act as a generator and vice versa
E. Demonstrate mutual induction
E. Transforming the voltage
Making model transformers
E. Demonstrate resistance heating and/or induction heating
Look at real transformers
Scheme of Work
8.5 Transformers
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Further work
8.6 Generating electricity
Literacy – Generating electricity from renewable
sources
SATIS materials (available from ASE)
106 The design game
Physics
Pupil book spread
107 Ashton Island – A problem of renewable energy
109 Nuclear power
201 Energy from biomass
403 Britain’s energy sources
601 Electricity on demand
Also SATIS 16–19 materials
21 Energy from the wind
46 Energy from the waves
63 Biogas
Role play on siting a windfarm from Teaching and Learning about the Environment Pack 3 (UYSEG)
available from ASE Booksales
Department of Trade and Industry provides data on fuel use in the UK www.dti.gov.uk/public/exp1.html
(Choose the Activities and Resources option, then Energy Statistics and then Energy in Brief)
Other information on renewable energy from University of Oregon (www.zebu.uoregon.edu/energy.html)
8.7 Power transmission
A1.1 Logic gates
A1.2 Inputs and outputs
E. Demonstration of low voltage model power lines
E. Logic circuits using AND, OR and NOT gates
(Also A1.2–A1.4)
E. Make a moisture detector and pressure pad
E. Experimental work with relays
E. Use AND and OR to switch on LEDs, motors
A1.4 More truth tables
E. Set up bistables using NOR gates
E. Set up latch circuit – Practical work using NAND and NOR gates
A1.5 The bistable and latch
A1.6 Potential divider
E. Measure the voltage across two parts of a potential divider for various resistance values
A1.7 Thermistors and LDRs
E. Set up control circuits using LDRs and thermistors
A2.1 Refractive index
ICT – Use a spreadsheet to show the relationship between angle of incidence and refraction (see 3.5)
E. Measure refractive index by sine/sine r
A2.2 How convex lenses work
E. Finding f for lenses
A2.3 Uses of convex lenses
V. Tacoma Bridge
ICT – Research on Tacoma Bridge collapse
Examine cameras and projectors
ix
Scheme of Work
A1.3 Electronic systems
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A2.4 Resonance
Further work
ICT – Spreadsheet to calculate wavelength from resonant length
E. Sonometer practical
A2.5 Resonance in strings
Physics
x
Pupil book spread
E. Resonance in open and closed tubes
A2.6 Resonance in pipes
A2.7 Interferance
E. Ripple tank for water waves showing reflection, refraction and diffraction
A2.8 The nature of light
A3.1 Linear motion
E. Verify Principle of Conservation of Momentum using an airtrack
A3.2 Projectile motion
A3.3 Momentum
A3.4 Rockets and jets
E. Make a model rocket
ICT – Look up data of rockets in current use
Use Internet to find out about jet engines
A3.5 Car crashes
A3.6 Measuring heat
E. Measure specific heat capacity
A3.7 Efficiency
E. Efficiency of a ramp
E. Efficiency of motor and other simple machines
Use Internet to obtain information about efficiency of power stations, cars etc
Scheme of Work
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Physics
Key Skills guidance
Introduction to Key Skills
In addition to GCSE double award (or separate
award) Science or GCSE Physics, students may be
completing a Key skills qualification. This involves
producing a folio of evidence, and Science or
Physics can provide some of this evidence.
There are six Key skills.
Three Key skills that lead to a qualification:
1
Application of numbers
2
Communication
3
Information technology
Three wider Key skills that are desirable, but do
not form apart of a qualification:
4
Improving own learning and performance
5
Working with others
6
Problem solving
If you want to find out more about Key skills,
contact the QCA website:
http://www.qca.org.uk/keyskills.
Key skills are at five levels: At GCSE Levels 1 and
2 are appropriate.
Level 1 helps students develop the basic skills that
are important for Key skills competence, and
recognises their ability to apply these skills to meet
given purposes within routine situations.
Level 2 builds on Level 1 by requiring students to
extend their basic skills. It recognises their ability
to take responsibility for some decisions about how
they select and apply these skills to meet the
demands of largely straightforward tasks. Level 2
corresponds to GCSE A–C.
The following sheets are designed so you can plan
opportunities for Key skills for each teaching
group. A copy of this sheet could be given to
students, to in-school Key skills Coordinators,
Senior Management and external visitors,
e.g. Ofsted Inspectors.
These sheets can be photocopied from the
Teachers’ Resource Pack, or downloaded from the
CD-ROM. If they are downloaded the name of the
school can be added in the header.
The OCR specification gives examples of where
Key skills can be met. The appropriate
opportunities are added to the table followed by
(1) if at Level 1, or (2) if at Level 2.
You should not try to find a large number of
opportunities. Students will have plenty of
opportunities in other subject areas. The ones
you suggest should be those that could provide
good evidence.
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Name of school _________________________________________________________
Teaching Group ______________________________________________
Year Group _________________________________________________________
Date ___________________
Teacher ______________________________________________
Level 1
Level 2
Candidates must be able to
Candidates must be able to carry through substantial activity that requires
them to
■
interpret straightforward information
■
carry out calculations, using whole numbers, simple decimals, fractions and
percentages to given levels of accuracy
■
interpret the results of their calculations and present findings, using a chart and
diagram.
Year 10
Physics
xii
Application of numbers
■
select information and methods to get the results they need
■
carry out calculations involving two or more steps and numbers of any size,
including use of formulae, and check their methods and their levels of accuracy
■
select ways to present their findings, including use of a graph, and to describe
methods and explain results.
Year 11
Term 1
Term 3
Key skills Summary sheet
Term 2
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Physics
Communication
Name of school _________________________________________________________
Teaching Group ______________________________________________
■
■
Date ___________________
Teacher ______________________________________________
Level 2
Level 1
■
Year Group _________________________________________________________
take part in discussions about straightforward subjects
■
help move discussions forward
read and identify the main points and ideas from documents about
straightforward subjects
■
give a short talk using an image to illustrate the main points
■
read and summarise information from extended documents
■
use a suitable structure and style when writing extended documents.
write about straightforward subjects.
Year 10
Year 11
Term 1
Term 3
xiii
Term 2
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Name of school _________________________________________________________
Teaching Group ______________________________________________
Year Group _________________________________________________________
Date ___________________
Teacher ______________________________________________
Level 1
Level 2
■
find, enter, explore and develop relevant information
■
present information, including text, images and numbers, using appropriate
layouts, and save information
Year 10
Physics
xiv
Information technology
■
identify suitable sources, carry out effective searches and select relevant
information
■
bring together, explore and develop information, and derive new information
■
present combined information, including text, images and numbers in a
consistent way.
Year 11
Term 1
Term 3
Term 2
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Name of school _________________________________________________________
Teaching Group ______________________________________________
Year Group _________________________________________________________
Date ___________________
Teacher ______________________________________________
Level 1
Level 2
Candidates must provide at least two examples of meeting the standard for LP1.1,
LP1.2 and LP1.3.
Candidates must provide at least two examples of meeting the standard for LP2.1,
LP2.2 and LP2.3.
LP1.1 Confirm their understanding of their short-term targets, and plan how these
will be met, with the person setting them.
LP2.1 Help set short-term targets with an appropriate person and plan how these
will be met.
LP1.2 Follow their plan, using support given by others to help meet targets.
LP2.2 Take responsibility for some decisions about their learning, using their plan
and support from others to help meet targets.
LP1.3 Review their progress and achievements in meeting targets with an
appropriate person.
Year 10
Physics
xv
Improving own learning and performance
LP2.3 Review progress with an appropriate person and provide evidence of their
achievements, including how they have used learning from one task to meet the
Year 11
Term 1
Term 3
xv
Term 2
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Name of school _________________________________________________________
Teaching Group ______________________________________________
Year Group _________________________________________________________
Date ___________________
Teacher ______________________________________________
Level 1
Level 2
Candidates must provide at least two examples of meeting the standard for
WO1.1, WO1.2 and WO1.3 (one example must show they can work in one-to-one
situations, and one that they can work in group situations).
Candidates must provide at least two examples of meeting the standard for
WO2.1, WO2.2 and WO2.3 (one example must show they can work in one-to-one
situations, one that they can work in group situations).
WO1.1 Confirm what needs to be done to achieve given objectives, including
responsibilities and working arrangements.
WO2.1 Plan straightforward work with others, identifying objectives and
clarifying responsibilities, and confirm working arrangements.
WO1.2 Work with others towards achieving given objectives, carrying out tasks to
meet your responsibilities.
WO2.2 Work cooperatively with others towards achieving identified objectives,
organising tasks to meet their responsibilities.
WO1.3 Identify progress and suggest ways of improving work with others to help
achieve given ojectives.
WO2.3 Exchange information on progress and agree ways of improving work with
others to help achieve objectives.
Year 10
Physics
xvi
Working with others
Year 11
Term 1
Term 3
xvi
Term 2
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Name of school _________________________________________________________
Teaching Group ______________________________________________
Year Group _________________________________________________________
Date ___________________
Teacher ______________________________________________
Level 1
Level 2
Candidates must provide at least two examples of meeting the standard for PS1.1,
PS1.2 and PS1.3.
Candidates must provide at least two examples of meeting the standard for PS2.1,
PS2.2 and PS2.3.
PS1.1 Confirm their understanding of the given problem with an appropriate
person and identify two options for solving it.
PS2.1 Identify a problem and come up with two options for solving it.
PS1.2 Plan and try out at least one option for solving the problem, using advice
and support given by others.
PS1.3 Check if the problem has been solved by following given methods and
describe the results, including ways to improve their approach to problem solving.
Year 10
Physics
Problem solving
PS2.2 Plan and try out at least one option for solving the problem, obtaining
support and making changes to their plan when needed.
PS2.3 Check if the problem has been solved by applying given methods, describe
results and explain their approach to problem solving.
Year 11
Term 1
Term 3
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Term 2
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Physics
Time allocation
Allocation of time to different parts of the
Physics specification
Double Award Physics is made up of eight units, and the Extension A for
Physics Separate Science has three additional units. Students are required
to study them all.
Different units require different lengths of time.
For Double Award, this analysis assumes 100 hours of Physics (along with
100 hours of Biology and 100 hours of Chemistry).
The 100 hours must include:
■
Teaching Ideas and Evidence (Sc1.1). This is built into the Student
Coursebook.
■
Teaching and Assessing (Sc1.2). Internally assessed coursework.
This is best built into the course so that students have the opportunities to
develop their practical skills.
The time required for End-of-block tests and Mock and Terminal tests is
not included in this allocation of time.
It is important to remember that GCSE papers, both at Foundation and
Higher levels, cannot examine KS3 content directly. The Check-up
sections in the Student Coursebook are intended to remind students of
what they have already done. There is a summary sheet of KS3 for each
teaching block which may help.
A suggested breakdown of time is:
1.
2.
3.
4.
5.
6.
7.
8.
Electric circuits
Forces and energy
Wave properties
Using waves
Radioactivity
Using electricity
Electromagnetism
6 hours
20 hours
13 hours
17 hours
10 hours
10 hours
11 hours
13 hours
Separate Physics
This assumes an additional 50 hours.
A1 Electronics and control
A2 Processing waves
A3 More about forces and energy
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16 hours
19 hours
15 hours
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Physics TB1
Activity 1.1
Aim
Materials required
You are going to study the effect of connecting resistors in series.
■
■
What to do
1
Check that you have everything you need for the experiment.
2
Set your multimeter to the 2 kΩ resistance setting.
3
Connect a single lead between the terminals, if there are more
than two terminals check with your teacher which two to use.
4
The meter should read zero, if it does not, ask your teacher for
help.
5
Use two crocodile clips and two connecting leads to connect
one resistor (R1) across the meter terminals as shown in Fig 1.
6
Repeat for a second resistor (R2).
7
Make a note of the values in a table like the one shown below.
R1 in kΩ
R2 in kΩ
■
■
Digital multimeter
Four crocodile clips
or two clip
component holders
Three connecting
leads
Resistors
0.000
R1 and R2 in series in kΩ
R1
Fig 1
0.000
8
Connect the two resistors in series, as shown in Fig 2 and
measure the resistance of the combination.
9
Make a note of the value in the third column of the table.
10
Repeat steps 5 to 9 for at least four more pairs of resistors.
R1
R2
Fig 2
Analysing your results
1
2
3
4
What can you say is always true when you compare the value
of the resistors on their own with the value when they are
connected in series?
Look carefully at the values in your table and try to find a
numerical pattern in your results. You may find it useful to use
a calculator.
What do you think will happen if you connect three resistors in
series?
Design a simple experiment to test your theory.
1
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Physics TB1
Activity 1.3A
Current–voltage graph for a metallic conductor
Aim
Materials required
You are going to study the way in which the voltage across a
metallic conductor affects the current flowing through it.
■
■
■
What to do
■
1
2
Wrap the wire round a 30 cm ruler making sure that no part of
the wire touches another part.
3
Attach a crocodile clip to each end of the wire to hold it in
place.
4
Connect up the circuit as shown in the circuit diagram.
5
Turn on the power supply and take a reading from both the
ammeter and voltmeter.
6
Record the values in a table like the one printed below.
voltage
in V
current
in A
■
■
■
2 m length of
constantan wire
One voltmeter
One ammeter
Five connecting leads
One power supply
Two crocodile clips
30 cm ruler
+
_
A
resistance
in Ω
wire
7
Use the equation resistance = voltage ÷ current to calculate the
resistance of the piece of wire for this pair of results.
8
Repeat steps 5 to 7 for at least five more values of current.
Do not use more than 12 V
V
3
Graph of voltage against current
for a metallic conductor
voltage (V)
Look carefully at the values of resistance in your table.
What can you say about the resistance of a metallic
conductor as the current flowing through it changes?
Now draw a graph of voltage against current for a
metallic conductor using axes as shown opposite.
1
2
Extension work
Turn the wire round and find out whether the direction
in which the current flows through the wire affects its
resistance.
4

Safety
The wire may get hot enough to burn you, especially if you use a
shorter length than 2 m or too high a voltage/current setting.
2
current (A)
M
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Physics TB1
Activity 1.3B
Current–voltage graph for the filament of
a light bulb
Aim
Materials required
You are going to study the way in which the voltage across the
tungsten filament of a light bulb affects the current flowing
through it.
■
■
■
■
■
What to do
1
2
Connect up the circuit as shown in the circuit diagram.
3
Turn on the power supply and take a reading from both the
ammeter and voltmeter.
4
Record the values in a table like the one printed below.
voltage
in V
current
in A
Light bulb in holder
One voltmeter
One ammeter
Five connecting leads
One power supply
+
_
resistance
in Ω
A
V
5
Use the equation resistance = voltage ÷ current to calculate the
resistance of the piece of wire for this pair of results.
6
Repeat steps 5 to 7 for at least 5 more values of current.
Do not use more than 12 V
3
4
5
Look carefully at the values of resistance in your table.
What can you say about the resistance of the tungsten filament
of a light bulb as the current flowing through it changes?
Graph of voltage against current
for the filament of a light bulb
What do you think is causing this change in the resistance
of the filament?
Now draw a graph of voltage against current for the
tungsten filament of a light bulb using axes as shown
opposite.
Turn the bulb round and find out whether the direction in
which the current flows through the filament affects its
resistance.
voltage (V)
1
2
current (A)

Safety
The light bulb will get hot enough to burn you. Keep fingers away!
3
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Physics TB2
Activity 2.1
Aim
Materials required
You are going to study the conditions needed to balance a metre rule.
■
■
What to do
■
■
1
2
Fasten the boss to the stand about 20 cm above the base and fasten
the short metal rod in the boss so that it is directly above the base.
3
Use the hole drilled at the 50 cm mark of the metre rule to
support the metre rule so that it is free to turn. Make sure that
the zero end of the scale is on the left.
4
Slide a giant paper clip onto each end of the metre rule. Move one
paper clip to the 10 cm mark and put the other at the 70 cm mark.
5
Hold the metre rule steady at one end and hang 2 N onto the
paper clip at the 10 cm mark.
6
Hang 4 N onto the paper clip at the 10 cm mark.
7
Let go of the metre rule but be ready to steady it. The chances
are that it will start to turn so get ready to catch it.
8
Now slide one of the paper clips, with the weights still
attached, backwards and forwards until the metre rule is
balanced. You probably won’t have to move the clip very far.
9
Draw a table similar to the one printed below with enough
space for ten sets of results.
weight 1, W1 in N
weight 2, W2 in N
2
distance 1, d1 in cm
Use the scale on the metre rule to measure the distance from
the 2 N weight to the metal rod, d1 and the distance from the
4 N weight to the metal rod, d2.
11
Put the values for these two distances into the table.
12
Repeat steps 4 to 11 for different weights and distances. There
are some situations where it seems to be impossible to balance
the metre rule, but you will find a way.
4
Stand
Rod
1N
10
W1
■
distance 2, d2 in cm
4
d1
■
Metre rule with hole
Short metal rod
Stand
Boss
Two giant paperclips
Two sets of 100 g
slotted masses (the
hanger and each mass
has a weight of
1 newton, N)
d2
W2
1N
Boss
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Physics TB2
Activity 2.1
1
2
3
4
Look carefully at the values in your table and try to find a link
between the values of weight and distance. You will probably
find it helpful to use a calculator.
Do you think that the data you have collected allows you to
come to a reliable conclusion about the effect of turning forces?
Suggest ways of making the data you collect more reliable.
Predict what will happen if you have two weights on one side
of the metal rod and one on the other. Join with another group
and use the apparatus from both groups to test your prediction.
5
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Physics TB2
Activity 2.2
Aim
Materials required
You are going to find the distance that a vehicle travels while
stopping over a range of vehicle speeds.
■
■
What to do
1
2
Use wooden blocks to lift one end of the plank about 15 cm.
Make sure the area beyond the end of the plank is clear.
3
Place the vehicle 0.30 m up the plank.
4
Let the vehicle go and time how long it takes for the vehicle to
reach the bottom of the plank.
5
Measure the distance the vehicle travels
along the floor before stopping. Measure
the distance from the front of the
vehicle to the end of the plank.
Repeat results.
7
Carry out the experiment again with
the vehicle starting at different
distances up the plank.
Record your results in a suitable table.
8
The following information may help you.
Average speed =
distance travelled
time taken
final speed = 2 × average speed.
2
3
4
6
■
0.30 m
0.15 m
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6
Speed, in m/s
Plot a graph of stopping distance (y-axis)
against speed of the vehicle at the
bottom of the plank (on the x-axis).
Answer the following questions.
Kim believes that the stopping distance is directly proportional
to the speed at the bottom of the plank.
(a) What does Kim think will happen to the stopping distance
if the speed of the vehicle is doubled?
(b) Do your results support Kim’s belief? What do you think?
Explain.
Which of the following is most likely to cause errors in your
experiment?
– Measuring the distance up the plank.
– Measuring the time the vehicle takes to run down the
plank.
– Measuring the stopping distance.
Would you have a better graph if you had taken more results?
If so which results would you try to get?
1
■
■
Stopping distance, in m
6
■
Wooden plank
(1 m–1.5 m long)
Free-moving vehicle,
e.g. toy car, dynamics
trolley
Metre rule
Stopwatch
Wooden blocks to
incline plank
Calculator
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Physics TB2
Activity 2.5
Friction
Aim
Materials required
You are going to find out how an object’s weight affects the friction
force between it and the surface it rests upon.
■
■
■
What to do
■
■
1
Think how you would expect the frictional forces to change
when the mass on the block increases.
2
Try to explain why, using your scientific knowledge.
3
4
Weigh the wooden block.
5
Pull the wooden block along using the forcemeter (see diagram).
Record the force necessary to pull the block along at a steady
speed.
6
Place 2 × 100 g masses on the block and repeat
the experiment.
7
Increase the mass on the block each time by
200 g until the mass is 1000 g.
8
Record your results in an appropriate table.
Wooden block with
screw eye
Wooden board
0–5 N forcemeter
Masses, 10 × 100 g
Access to balance
Friction force, in N
2.5
2.0
1.5
1.0
0.5
0
0
200
400
600 800
Mass, in g
1000 1200
1
2
3
4
5
Plot a graph of the frictional force in N (on the y axis) against
the total mass in g (on the x axis).
What can you conclude from your experiment?
Does this support your original prediction? Use the data to
show this. If it does not support your prediction, how is it
different?
What are the most likely errors in your experiment?
Suggest other factors that might affect the frictional force.
7
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Physics TB2
Activity 2.7
Aim
A margarine tub is fired across the floor using an elastic band.
Your teacher will demonstrate this to you.
Your task is to identify the factors that affect how far the tub goes
and then to study the effect of varying one of them.
What to do
Your task is in four parts
Planning
Obtaining the Evidence
Analysing the Evidence
Evaluation
First make a list of the factors that might affect how far the tub will
travel across the floor.
Choose the factor you are going to investigate.
Make a list of all the apparatus you will need.
Write a plan on how you intend to carry out the investigation.
What are you doing to ensure a fair test?
Can you make a prediction?
Try to support your prediction with your scientific knowledge and
understanding.
Plan a preliminary experiment and be prepared to make changes if
it does not work.
Now carry out your experiment collecting sufficient data.
Analyse these data. Do your findings support your prediction?
Finally evaluate your experiment. Did you collect enough data?
Did you have any anomalous results? Could you suggest any
improvements in your methods if you were to do it again?
Now write up your investigation.
8
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Physics TB2
Activity 2.9
Aim
Materials required
You are going to measure the time it takes you to react to
something and relate this time to road safety.
■
Half-metre rule
What to do
1
You will need to work in pairs and will need to use the graph
printed below to measure your reaction time.
2
The graph shows how long a rule takes to fall different
distances.
50
45
40
35
distance fallen (cm)
M
30
25
20
15
10
5
0
0
0.05
0.1
0.15
0.2
0.25
0.30
0.35
time (s)
3
The graph shows that it takes 0.2 seconds for the rule to fall
20 cm.
4
Copy the table below and use the graph to complete it.
distance fallen by
rule in cm
time taken in s
5
10
18
28
5
Check your answers with your teacher before going any further.
6
One person is now going to let the rule go and the other person
is going to catch it, but the second person will not know when
the rule is going to be released.
쑺
continued
9
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Physics TB2
Activity 2.9
7
The first person holds the rule as shown in Fig 1, with the zero
mark at the bottom, and then releases it without warning. The
second person has to catch it by moving their fingers together,
Fig 2.
8
The distance marked ‘x’ on Fig 2 is the distance the rule has
fallen. Make a note of the distance.
9
Repeat ten times each and calculate the average of your results.
1
2
3
4
Use the average distance fallen and the graph to measure the
average time for you to stop the rule falling.
This is your reaction time. If you were riding a bicycle or
driving a car it might take you this time to put on the brakes if
you saw a hazard in front of you.
Use the equation distance = speed × time to calculate how far a
vehicle travelling at different speeds would travel while you
reacted to a hazard. Put the distances in a copy of the table
printed below.
speed
in mph
speed
in m/s
20
9
30
13
50
22
70
30
Fig 1
distance travelled
in m
In a real driving situation your reaction time would probably be
much longer.
10
10
M
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Physics TB2
Activity 2.10A
Aim
Materials required
You are going to find the terminal velocity of ball bearings.
■
This experiment involves dropping steel ball bearings of two
different diameters into a tall measuring cylinder containing motor
oil. The measuring cylinder is divided into four sections by three
elastic bands (see diagram). The time is taken for each ball bearing
to fall from A to B and then from B to C. You can work out the
terminal velocity in each case. From these results you can conclude
how the terminal velocity changes as the diameter of the ball
bearing changes.
■
■
■
■
■
■
What to do
■
1
Check that you have the equipment required for the
experiment.
2
Read ‘safety note’ and ask your teacher if you need anything
explaining.
3
Put elastic bands around the measuring cylinder as shown in
the diagram. Make sure the distance between A and B and B
and C is the same. Measure this distance.
4
Fill the measuring cylinder with motor oil.
Measuring cylinder
3
(500 cm )
Fresh motor oil
Small elastic bands
Two small steel ball
bearings (one of
diameter 4 mm and
one smaller)
30 cm ruler
Stopwatch
Magnet
Tissues
500 cm3
A
300 cm3
B
100 cm3
C
Practical
5
Drop one of the ball bearings from above the centre of the
surface of the oil.
6
Start timing when the ball bearing passes A and take the time
when ball bearing passes B and again when it passes C.
7
The ball bearing can be recovered by placing the magnet on the
outside of the measuring cylinder and moving it slowly up the
outside of the measuring cylinder until the ball bearing reaches
the top of the cylinder. It can then be dried with a tissue.
8
Repeat the experiment until you are satisfied with your results.
9
Now carry out the same procedure with the smaller ball
bearing.

Safety
Avoid skin contact with
motor oil. Use towel or
tissue. Wash hands after
you have finished. Do not
pour any oil into a sink or
drain.
Do not throw the motor oil away at the end.
Obtaining and analysing results
1
2
3
4
5
Record the results of your experiments in a suitable table.
Ask your teacher if you need help in devising a table.
Work out the terminal velocity for each ball bearing.
How do you know that each ball bearing reaches its terminal
velocity?
Have you collected enough evidence to be sure about the
relationship between the terminal velocity and the diameter of
the ball bearing?
Suggest improvements that could be made to the procedure you
have used.
11
11
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Physics TB2
Activity 2.10B
Aim
Materials required
You are going to plot velocity–time graphs for
a golf ball and a ping-pong ball being pulled
downwards by the force of gravity.
Resistive forces
■
■
Gravitational forces
You can process your data and plot the graph manually or use a
spreadsheet and linked graph-plotting package.
■
■
■
■
Ticker timer
Ticker tape
Golf ball
Ping-pong ball
Power supply
Sellotape
What to do
1
Check that you have everything you need and set up your
apparatus, as shown in Fig 1.
2
The ticker timer should be at least 1.5 m above the ground.
3
Make sure that there is nothing to get in the way of the golf
ball as it falls.
4
Cut a piece of ticker tape so that it is just shorter than the
distance between the time and floor.
5
Fasten the tape to the ball and thread the tape through the
timer.
6
Check that the ball falls freely and pulls the tape easily
through the timer.
7
Repeat step 4, but turn on the power supply before letting the
ball fall.
8
Repeat steps 2 to 7 using a ping-pong ball.
Experimental
arrangement
Ticker timer clamped to stand
1.5 m to ground
To power
supply
Fig 1
Obtaining and analysing results
1
2
3
4
5
6
7
8
Observe the dots made by the timer and measure the distance
between each dot and the next, starting with the pair which
were made first (see Fig 2).
Enter your results into a table like the one printed below, or a
suitable spreadsheet.
The timer makes 50 dots every second so the time between
dots being made is 0.02 seconds.
The distance between dots is the displacement of the ball in
each 0.02 s time interval.
Using the equation velocity = displacement ÷ time calculate
the velocity for each 0.02 s time interval.
Use your results to plot graphs of velocity against time for
both balls.
What do the shape of the graphs tell you about the way in
which the balls fall?
Use your ideas about the forces acting on the balls to explain
the shape of the graph.
time in s
golf ball dist in mm
golf ball vel in mm/s
0
0
0
0.02
0.04
12
a
b
c
Fig 2
a = displacement in first 0.02 s
b = displacement in second 0.02 s
c = displacement in third 0.02 s
M
T
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Physics TB2
Activity 2.11
Aim
Materials required
You are going to investigate why fast food outlets bother to put a
lid on hot drinks.
■
■
■
What to do
1
■
Check that you have all you need for the experiment.
Temperature
sensors
■
Lid
■
■
Polystyrene cups
Interface
Computer
3
2
Measure 150 cm of cold water in a measuring cylinder and
transfer carefully to a polystyrene cup. Mark the level with a
waterproof marker. Repeat for the other cup.
3
Drain the cups, set up the sensor equipment as shown.
4
Fill each to the mark quickly with near-boiling water from a
kettle, fit the lid on one and begin recording.
5
After a suitable time (e.g. 10–15 mins.) stop the recording and
print out the results.
2
3
4
5

Safety
Use only cups designed for
very hot liquids. Other
types will collapse. take
care pouring boiling water
into lightweight cups; it is
easy to tip them over.
Look at your results and see which vessel cooled quicker. Give
a scientific explanation for your answer based on methods of
heat transfer as well as saying why it is worth having a lid.
Examine the cooling rates by picking a suitable temperature
interval, e.g. 80–75°C and reading off the time each vessel takes
to cool through that range. Work out the average rate of cooling
using the formula given.
Temperature
Cooling rate = Temperature change (˚C/min)
change
Compare the cooling rates for each vessel
Time change
and work out how much faster one cools
(e.g. the one without the lid cools three
times as fast between 80 and 75°C.)
Examine if the relative rate of cooling is
the same for all temperature ranges.
Choose from the following and adapt the
method to answer one or more of the
Time (m)
following questions
Time change
a) What difference does the cup
material make? (N.B. see ‘safety’ note!)
b) What difference does the cup size make?
c) Is it worth using a double cup?
d) Do shiny teapots keep the heat in better than dull ones?
e) Do different metals lose heat at the same rate?
f) What difference does it make if the seal on a vacuum flask
is broken?
Temperature
1
3
250 cm measuring
cylinder
Waterproof marker
Two polystyrene cups
and a lid
Access to kettle for
hot water
Two temperature
sensors and interface
Computer and
datalogging software
Access to other cups,
metal calorimeters
and vacuum flasks
(for extension work)
13
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Physics TB3
Activity 3.4
Aim
Materials required
You are going to study the behaviour of a ray of light when it is
reflected by a plane (flat) mirror.
■
■
■
What to do
■
■
1
2
Draw a line, about 10 cm long, on the sheet of plain paper using
a ruler and then draw some short lines to represent the
silvering on the mirror (Fig 1).
3
Using a protractor draw a dashed line at right angles to the
mirror and label it ‘normal’ (Fig 2).
4
Draw a line like the one shown in Fig 3, measure the angle
marked, i and write down its value in a table like the one
printed below.
■
■
■
Ray box
Single slit
Power supply
Protractor
Plain paper
Pencil
Ruler
Plane mirror and
holder
A
Fig 1
B
A
Fig 2
angle i
angle r
normal
B
Use a stand for your mirror and arrange the mirror so that it
stands vertically.
5
Fig 3
A
C
normal
Put the mirror against the line marked AB. If you are using a
plastic mirror put the front of the mirror against the line and if
you are using a glass mirror put the back of the mirror against
the line.
6
Connect your ray box to the power supply and use a single slit
to make one ray of light shine along the paper.
7
i
B
Fig 4
C
A
normal
Shine the ray of light along the line that starts at C so that it
hits the mirror, you should see a ray of light reflected from
the mirror.
8
9
Mark the position of this ray with two crosses (Fig 4).
10
Draw in the line taken by this reflected ray and use your
protractor to measure the angle marked r (Fig 5). Write down its
value in the table.
11
Repeat steps 4 to 10 for at least five more lines where the angle
i is different.
i
+
+
Fig 5
C
normal
i
5
What do your results tell you about angles i and r?
Are your results reliable?
How could you make your results more reliable
Join with another group and arrange two mirrors to make a ray
of light follow the path shown in Fig 6.
How could an arrangement like this be used?
14
reflected
ray of light
A
r
+
1
2
3
4
B
+
Fig 6
B
reflected
ray of light
M
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Activity 3.5A
Physics TB3
Aim
Materials required
You are going to study the behaviour of a ray of light when it passes
through a rectangular perspex block.
■
■
■
■
What to do
■
1
2
Put the perspex block onto the piece of paper so that it rests on
its biggest face and then draw round the block in pencil (Fig 1).
3
Remove the block and then using a protractor draw a line at
right angles to the perspex block and mark the end of the line
with a letter A (Fig 2).
4
Put the block back in place.
5
Connect your ray box to the power supply and use a single slit
to make one ray of light shine along the paper.
6
Shine the ray of light along the line that starts at A so that it
hits the block, you should see a ray of light coming out of the
opposite side of the block.
7
Mark the position of this ray with two crosses (Fig 3).
■
■
Ray box
Single slit
Power supply
Plain paper
Perspex block
Protractor
Pencil and ruler
Fig 1
Fig 2
8
Remove the block and use the two crosses to draw in the path
of the ray of light as it emerges from the block.
9
Repeat step 2, remove the block and then draw a line to the
block similar to the one in Fig 4. Label the line B.
10
Shine the ray of light along the line that starts at B so that it
hits the block, you should again see a ray of light coming out of
the opposite side of the block.
11
Repeat steps 7 and 8.
A
Path of
ray of light
Fig 3
+
+
1
2
3
Use the two diagrams you have drawn to predict the path taken
by the ray as it travels through the block. Remember that light
travels in straight lines.
What can you say about the behaviour of light as it travels from
one material into another?
Does the behaviour of the light depend on the angle at which
the ray hits the boundary?
15
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Physics TB3
Activity 3.5B
Aim
also A2.1
Semi-circular block
You are going to investigate the
relationship between angle of
incidence and angle of refraction.
Narrow light beam
Materials required
■
Narrow
slits
■
■
What to do
Check that you have everything
you need for the experiment.
1
■
■
Ray box
■
■
2
Place the block on a sheet of
plain paper, carefully trace round it and mark the centre of the
flat face as accurately as possible.
3
Use a protractor to mark in the ‘normal’ line at 90° to the
centre point.
4
Mark in lines showing suitable angles of incidence (i)
between 10° and 70°. Plan for a sensible number of values.
Replace the block.
Normal
10˚
Use the ray box to shine a ray along each incidence line in
turn. Mark the path of the ray as it leaves the block. Extend
it back as shown and measure the angle of refraction (r) as
accurately as possible.
5
Glass or plastic
semi-circular block
Sheet of A3 paper
Raybox with narrow
slit
Protractor
Ruler
Sharp pencil
Access to computer
with spreadsheet
package such as
EXCEL
Outline
of block
Guide lines
If you have time, repeat the experiment with a
block made from a different material.
6
r
Angle of
incidence
Find a straight-line (proportional) relationship
between the angles of incidence and refraction
using a spreadsheet.
Put in the values of the angles of incidence and refraction then
use the X–Y plot function to examine the relationship. Try
other possibilities which involve maths functions of angles
such as TANGENT, SINE or COSINE. Print out a graph which
shows the best straight-line relationship. Write out a formula
to show this relationship.
Were your data accurate enough? What simple improvements
could be made to get more reliable data?
Find out what is meant by Refractive Index. What advantage is
there for people who wear glasses in having lenses made from
glass or plastic with a high refractive index?
1
2
3
4

Safety
Do not knock glass blocks against each other. Bits of glass may fly off.
16
i
Angle of
refraction
M
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Physics TB4
Activity 4.1
Aim
Materials required
You are going to observe that white light can be split into its
constituent colours and relate the colour of light to the wavelength
and frequency of the electromagnetic waves. This experiment will
help you to develop practical and observational skills.
What to do
■
■
■
■
■
1
2
Set up the apparatus as in the figure.
3
Direct a beam of light on to the face of the prism and
observe the light that leaves the opposite face by
placing the screen in a suitable position.
4
Observe the appearance of the spectrum.
5
Write down the colours in the order in which they
appear on the screen, starting with red.
Power supply
12 V, 24 W lamp in
holder
Slit to produce a
narrow beam
Isosceles prism
White screen which
will stand vertically
Prism
White light
White screen
6
Which colour of visible light undergoes the greatest
change in direction?
7
Where does the change in direction take place?
8
Note that the change in direction is caused by the change in
speed when light passes from one material into another.
1
2
3
4
How does the speed of light change as it passes into the prism?
Which colour of light has the greatest change in speed as it
passes into the prism?
Which colour of light has the greatest speed in the prism?
The table shows typical wavelengths and frequencies of red,
green and blue light.
colour
5
6
typical wavelength in m
typical frequency in Hz
red
6.0 × 10
-7
5.0 × 10
14
green
5.0 × 10
-7
6.0 × 10
14
blue
4.0 × 10
-7
7.5 × 10
14
Complete the sentence:
As the wavelength of light increases, its frequency
_______________.
Which colour of light has the (i) longest wavelength?
(ii) greatest frequency?
What is the relationship between the change in speed of light as
it passes into and out of a prism and its wavelength?
17
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Physics TB4
Activity 4.6–4.8
Aim
ICT required
You are going to use the internet to find data on recent
earthquakes, examine the evidence they provide for tectonic plate
theory and use ICT to produce a report.
What to do
1
Prepare a presentation which is part of a larger presentation on
the topic of ‘Earthquakes’. Your section of the work is ‘the
Pattern of Recent Earthquakes’ and it is important that most of
your information is as up to date as possible. You can decide
exactly what is meant by ‘recent’ and you are at liberty to add
earlier information which will reinforce your findings.
2
Your presentation can be in the form of
a)
a computer based presentation package (e.g. Powerpoint)
b)
a talk which uses OHP transparencies
c)
a magazine article.
In each case, you will need to provide copies of all text, graph
and diagram work.
3
Your target audience will want to know answers to the
following:
■
■
■
■
■
■
■
■
How many earthquakes are there worldwide each day?
Which has been the biggest one recently?
How are they different in their destructive power?
How is the destructive power calculated?
Where do they tend to occur and what does this tell us
about the structure of the Earth?
How are they located?
What earthquakes have we had in this country lately and
why don’t we get very big ones?
What is happening about predicting earthquakes?
4
You should begin your search by using a search engine to find
sites which contain ‘earthquake’ but use other key words to
narrow down the search so that you find a small number of
sites which are relevant to your task and which can be
examined easily.
5
When you have found useful information, select carefully what
you need and store it in a form which can be used in your final
presentation. If in doubt, save it, you can always discard it
later. Keep a record of the sites you use so that you can quote
them in your report or go back to them for extra information if
you need to.
18
■
Computer with
internet connection
– word processor
– spreadsheet
– desktop publisher
– presentation
package,
e.g. Powerpoint
– access to colour
printer
–
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Physics TB5
Activity 5.2
demonstration
Radioactive source
Aim
In this experiment you are going to distinguish
between the three main types of radioactive
emission in terms of their penetration. You will be
able to relate the penetration of radioactive
emissions to the size of the emission and to develop
skills in the safe handling of radioactive materials.
Absorber
Counter
Detector (GM tube)
What to do
1
Describe the key points in the procedure.
2
Give two safety precautions that should always be observed
when handling radioactive materials.
3
Measure the total number of counts in 1 minute and record the
results in the table, at the bottom of the page.
1
2
3
4
5
Which of the three sources was decaying at the greatest rate?
Explain how you can tell.
Which source has the least penetration?
Alpha sources are used in domestic smoke alarms. Explain why
the radiation from these sources does not present a threat to
the people who live in the house.
Explain whether it is valid to conclude that alpha radiation is
totally absorbed by a 5 cm air gap.
Suggest why the count rate detected from the beta and gamma
sources is reduced by a 5 mm air gap.
source
absorber
background radiation
none
alpha
none
number of counts in 1 minute
5 cm air
3 mm aluminium
beta
none
5 cm air
3 mm aluminium
2 mm lead
gamma
none
5 cm air
3 mm aluminium
2 mm lead
2 cm lead
19
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Physics TB5
Activity 5.3
Aim
Materials required
You are going to simulate radioactive decay using a random number
generator and then use the data to find a half-life.
What to do
1
Set the random number generator to select 240 numbers at
random between 1 and 6. This means setting the limits at 0
and 7.
2
Generate the random numbers and print them out.
3
Count up the number of sixes in the list. Suppose there are x
sixes chosen.
4
Repeat but generate (240−x) numbers. Print these out.
5
Count up the number of sixes in the list. Suppose there are y
sixes.
6
Repeat but generate (240−x−y) numbers.
7
Continue repeating the procedure until you are generating less
than 25 numbers (i.e. about 10% of the number you started
with).
8
Record your results in a suitable table.
1
2
3
4
5
Plot a graph of the number of random numbers generated (on
the y-axis) against the number of times numbers are generated
(on the x-axis).
Describe how you would monitor the activity of a radioactive
sample.
Describe the shape of the graph.
The half-life is the average number of times numbers have to
be generated for the number to fall to half its value, e.g. 240 to
120 or 180 to 90. Take four different starting numbers and find
the average number of number generations required each time
to get to half the original value. Work out an average.
Suggest how this experiment could be adapted to improve the
precision of the results.
20
■
■
■
Computer
Random number
generator programme
Access to a printer
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Physics TB7
Activity 7.3
electric charge and current:
Teacher demonstration
Aim
In this experiment you will discover that an electric current is a
flow of electric charge. You will develop observational skills and
analyse how the charge is carried by a conducting ball. You will
also discover how to change the size of the electric current
produced.
Safety
■
This is a teacher demonstration
experiment only.
■
The dome of the van de Graaff
generator can become charged
to a very high voltage.
■
The van de Graaff generator
must not be touched while the
experiment is in progress.
■
The dome of the van de Graaff
generator must not be touched
after the experiment until the
teacher has checked that it is
fully discharged.
van de Graaff
generator
Small conducting ball
suspended by nylon thread
Sensitive ammeter
(e.g. light beam
galvanometer)
H
H
2 metal plates clamped by
insulating handles H
What to do
1
Describe the key points in the procedure.
2
Answer the following questions.
1
2
Explain why the sensitive ammeter indicates a current.
Mark the charges, if any, on the ball at each stage of its motion
as shown in the diagrams below.
+
+
+
–
–
–
(a)
+
+
+
–
–
–
(b)
+
+
+
–
–
–
(c)
Use the diagrams to explain why the ball keeps oscillating
between the plates.
4 What happens when the plates are moved closer together to
(a) the movement of the ball?
(b) the ammeter reading?
Account for the changes you have mentioned in (a) and (b).
3
21
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Physics TB8
Activity 8.2
Aim
Materials required
You are going to use datalogging to look at the speed of a motor and
how it changes with current, voltage and load.
■
Light unit
12V
■
■
Flywheel
with slit
■
Computer
■
Motor
12V
Variable
power
supply
■
Light
sensor
■
V
Interface
A
■
■
What to do
1
Make sure that you have all that you need for the experiment.
2
Set up the equipment as shown above.
3
Set the computer to record for 30 seconds.
4
Select a low voltage, enough to get the motor turning slowly,
switch on the motor and begin recording.
5
Note values of voltage and current.
6
Repeat for different voltage/current settings. You will need to
choose the values and the range which would be appropriate for
reliable results.
7
Calculate the speed of the motor for
each run as in the diagram below.
Tabulate these values and plot
graphs of motor speed against
current, voltage and power
consumption. You may wish to use
a spreadsheet to do this section of
the task, as well as the calculation
of motor speed.

Safety
Keep fingers, ties, long hair
etc. well away from
spinning flywheel.
• Note time (T) for 10 gaps
• Time for 1 rotation = T
10
• Rotations per minute
= 60 = 600
T
(T10)
Light level
8
Time for 10 gaps
Computer with
and interface
Printer
Light sensor and light
unit
Ammeter
Voltmeter
Variable power
supply
Electric motor fitted
with flywheel
Suitable leads
Access to a
spreadsheet such as
Excel
Time (s)
1
2
What relationship does the motor speed have to the linked variables voltage, current and
power?
Use the experience gained from using the basic method to plan a variation which looks at the
effect of ‘load’ on the motor speed at a given voltage.
22
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Physics TB8
Activity 8.3
Aim
Materials required
You are going to use datalogging to link the size of an induced emf
with the speed of change of magnetic field using a voltage sensor
and light gates.
■
■
Magnet
Coil
unit
■
■
■
Tube
Computer
■
■
Foam
rubber
Computer and
Glass or plastic tube
approximately 1.5 m
long by 30 mm
diameter
Light gates
Voltage sensor
Coil of wire with
known number of
turns
Small cylindrical
magnet
Foam rubber
Interface
What to do
2
3
4
5
6
7
Make sure that you have all you need for the experiment.
Set up the apparatus as shown, with the light gates being a known distance (e.g. 15 cm) apart.
Set the datalogging software to record the voltage across the coil and the time between the
light gates being activated. If the software allows it, set it to calculate the speed of the
magnet between the light gates, otherwise you will have to calculate the speed manually
from the time value for each experiment.
Set a recording time of 5 seconds or as near above this as the
Voltage
software allows.
Start recording and, after a delay of one second, drop the
magnet through the tube.
Note from the computer, the time or speed of the magnet
and the peak-to-peak induced voltage.
Repeat the experiment several times, each time increasing
the distance between the end of the tube and the coil so that
the speed of the magnet increases. You will have to decide
Time
the number of different speeds and what to do if you wish to
increase the range of speeds.
Peak-to-peak
voltage
1
1
2
3
4
5
6
Plot a graph of induced voltage against speed to determine the relationship between the two.
You could put the results into a spreadsheet such as ‘Excel’ and use this to draw a line of best
fit.
Determine a mathematical relationship between the speed and induced voltage.
Explain the form of the induced voltage recording.
Why does the magnet’s speed not increase linearly with distance?
The induced voltage recording is not always symmetrical about the null point. Suggest
reasons for this.
Could the light gates be closer to get a more reliable measure of the speed? Explain your reasons.
23
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Physics TB8
Activity 8.4
Aim
Materials required
You are going to investigate electromagnetic induction to demonstrate
that a voltage is induced in a conductor when the magnetic field
through it changes. You will find out how the size of the induced
voltage depends on the rate at which the magnetic field changes and
also how the direction of the induced voltage can be reversed. This
will help you to develop practical and observational skills.
■
■
■
■
■
■
■
Sensitive ammeter
Primary
coil
Secondary
coil
What to do
1
Make sure you have all the equipment for the experiment.
2
Wind a coil of 2–3 cm diameter and 15–20 turns and connect it
to a sensitive ammeter which can detect currents in either
direction.
3
Complete the table of results, by comparing the ammeter
deflection in each case.
action
ammeter indication
N pole moved slowly towards coil
N pole moved rapidly towards coil
magnet held stationary inside coil
S pole moved towards coil
current in primary coil switched on
current in primary coil remains on
current in primary coil switched off
1
2
3
4
5
6
7
How is the size of the induced voltage affected by the speed of
movement of the magnet?
State two ways of reversing the direction of the voltage induced
by moving a magnet towards a coil of wire.
Explain why there is no induced voltage when the magnet is
stationary inside the coil.
Explain why a voltage is induced in the secondary coil when a
direct current is switched on in the primary coil.
Explain why there is no induced voltage in the secondary coil
when a steady current passes in the primary coil.
Explain why, when the current in the primary is switched off, the
voltage induced in the secondary coil is in the opposite direction
to that when the current in the primary coil is switched on.
If the current in the primary coil were to be switched on and off
repeatedly, what type of current would pass in the secondary coil?
24
■
2 × 1 metre length of
single strand wire
Sensitive ammeter
Strong bar magnet
1 pair of c-cores
1.5 V d.c. cell in
holder
A switch
Connecting leads and
crocodile clips
Wire cutters/strippers
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Physics TB8
Activity 8.5
Aim
Materials required
You are going to perform an experiment to help you understand
that electromagnetic induction occurs when the magnetic field
through a conductor changes. You will also develop observational
skills and find out the difference in action and construction
between a step-up and a step-down transformer. This will help
you to relate step-up and step-down transformers to some
everyday uses.
■
■
■
■
Coils of wire
Two c-cores
Lamp
d.c. source
Low-voltage a.c.
source

What to do
1
■
Wind two separate 15 turn coils of wire onto c-cores as in the
diagram.
Iron c-cores
1.5 V d.c.
supply
Primary
coil
Secondary
coil
Safety
In these experiments,
you may need to
lengthen the wire that
you are using.
It is permissible to do
this by joining two
wires together, by
twisting the bared ends
but if you do this, cover
the join with insulating
tape.
This method of joining
wires is only
permissible because the
voltages used are low
and the connections are
only temporary.
DO NOT ever use this
method of joining wires
that carry mains
voltages as this could
result in a fire or
someone receiving a
fatal electric shock.
2 V a.c.
supply
2
Connect one coil to a lamp, the brightness of which indicates
the size of the induced voltage.
3
Connect a d.c. source to the primary coil and note that the
lamp does not light.
4
Connect a low-voltage a.c. source to the coil and use the
brightness of the lamp as a reference.
5
Change the number of turns of wire on the secondary coil and
note the brightness of the lamp.
continued
쑺
25
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Physics TB8
Activity 8.5
Obtaining and analysing evidence
1
2
Complete the table of results, at the bottom of the page.
A voltage is induced in a conductor when the magnetic field
through it changes. Explain why the lamp does not light when
a direct voltage is connected to the primary coil.
input (primary)
voltage
3
4
5
6
number of
primary turns
number of
secondary turns
1.5 V d.c.
15
15
2.0 V a.c.
15
15
2.0 V a.c.
15
10
2.0 V a.c.
15
20
2.0 V a.c.
15
25
2.0 V a.c.
15
30
lamp brightness (off, dim,
normal or bright)
normal
Explain why the lamp lights when an alternating voltage is
applied to the primary coil.
A step-down transformer decreases the size of an alternating
voltage. What is the relationship between the numbers of turns
on the primary and secondary coils in a step-down transformer?
A step-up transformer increases the size of an alternating
voltage. What is the relationship between the numbers of turns
on the primary and secondary coils in a step-up transformer?
Which type of transformer is used:
(a) to increase the mains voltage from 240 V to 5000 V to
accelerate the electrons in a television tube?
(b) to decrease the mains voltage from 240 V to 12 V to operate
a low-voltage garden light?
26
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Physics TB8
Literacy activity 8.6
Generating electricity from renewable
sources
In recent years most of the electricity has been generated from
burning fossil fuels such as coal and natural gas. Only about 2–3%
has been generated from renewable sources.
The UK Government has set targets:
■
to produce 5% of the electricity used from renewable sources
by 2003
■
to produce 10% by 2010.
Three ways of producing electricity from renewable sources are to
use water, biomass and wind.
Download Sustainable Power – at a Price from Electricity
Association (www.electricity.org.uk).This is to be used as reference
material but students may seek information elsewhere. It may be
beneficial if students are given homework to read the article and to
do some research themselves.
Divide students into four groups.Each group is allocated one of the
following.
1.
2.
3.
4.
Supporters of generating electricity from coal and natural gas.
Supporters of generating electricity from water.
Supporters of generating electricity from biomass.
Supporters of generating electricity from wind.
Each group should appoint a leader and then under his/her
leadership produce a table listing the advantages of their method of
generating electricity and the disadvantages of the others.
They then write a report promoting their fuel. This should be
between 200 and 300 words. Approximately an hour should be
spent on this.
One member of each group then reads out their report.
The whole class is then asked to vote on the best method for
generating electricity in the future, on the evidence provided by the
reports.
Follow up:
Each student writes an essay on the fuels that are available for
generating electricity in the 21st century.
N.B. There are no Teachers’ and technicians’ notes for this activity.
27
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Physics TBA1
Activity A1.1–A1.3
Logic circuits using AND, OR and NOT
gates
Materials required
Aim
■
You will set up logic circuits using AND, OR and NOT gates for a
variety of input sensors, such as light, temperature and moisture
sensors and draw up results in the form of truth tables.
■
■
What to do
Set up the logic circuits shown below, using the input sensors
suggested. (Your teacher will tell you how to connect up the
particular type of logic unit in your laboratory.)
1
For each circuit complete the truth table, where 1 represents a
high signal and 0 a low signal.
2
3
If time permits repeat for other combinations of input sensors.
4
(H) Combine AND and NOT and OR and NOT gates.
5
(H) Repeat using NAND and NOR gates.
6
Remember: the resistance of a light dependent resistor (LDR) is
low in the light and the resistance of a thermistor is low when
hot.
Inputs
Input sensors – light and temperature sensors
Output
A
B
0
0
0
1
1
0
1
1
OR gate truth table
Inputs
Inputs
A
Output
B
AND gate
Input sensors – two light sensors
Output
Inputs
A
Output
B
A
B
0
0
0
1
1
0
1
1
28
■

Complete the following truth tables.
AND gate truth table
■
■
1
■
Low-voltage (5 V)
power supply
AND, OR and NOT
gates – at least one of
each
At least two input
sensors chosen from:
light, temperature,
moisture sensors
Suitable output such
as LED, lamps or
buzzer
Connecting leads
(H) NAND and NOR
gates – at least one of
each
Extra gates and input
sensors if you go on
to combine logic
gates
OR gate
Safety
Electronics apparatus
must only be used with
a low-voltage power
supply (5 V). Always
make sure that the
power is switched off
when setting up or
changing your circuits.
Get your teacher to
check your circuits
before switching on.
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Physics TBA1
NOT gate truth table
Activity A1.1–A1.3
Input sensor: (i) light sensor
(ii) temperature sensor
(i)
Input
Input
Output
Output
0
NOT gate
1
(ii)
Input
Output
0
1
2
Suggestions for further experimental work:
(a) Repeat the above experiments using other combinations of
sensors.
(b) Suggest practical applications for each logic system.
(c) (i) Combine two or more logic gates and draw up a truth
table from your results.
(ii) See if you can deduce the result using the truth tables
for AND, OR and NOT gates obtained previously.
H level
1
2
3
(a) Combine NOT and AND gates and produce a truth table
from your results.
(b) Use a NAND gate and show that the truth table obtained is
the same as that in (a).
(a) Combine NOT and OR gates and produce a truth table
from your results.
(b) Use a NOR gate and show that the truth table obtained is
the same as that in (a).
(a) Combine two or more logic gates, including at least one
NAND and/or NOR gate, and draw up a truth table from
your results.
(b) See if you can deduce the outcome using the truth tables
obtained previously.
29
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Physics TBA3
Activity A3.6
Aim
Materials required
You are going to calculate the amount of energy transferred from
electricity to heat by an immersion heater and develop skills in
application of number which will enable you to understand that
different materials require different amounts of energy to raise the
temperature by the same amount.
What to do
Set up the
apparatus as
in the
diagram.
+
Heater
12V supply
A
00.00
Using a 1 kg metal block, record the intial temperature.
Switch on the immersion heater until the temperature has
risen by about 10°C.
4
Record the current, voltage and time for which the heater is
switched on.
5
Record the maximum temperature reached after the heater has
been switched off.
6
Repeat the procedure for other metals and complete the table at
the bottom of the page.
5
■

3
3
4
■
1 kg blocks of
aluminium, iron,
brass and copper
Stopwatch
Laboratory
thermometer
12 V power supply
0–5 A ammeter
0–15 V voltmeter
12 V, 24 W
immersion heater
Stopwatch
2
2
■
■
Circuit diagram
V
1
■
■
Thermometer
1
■
Safety
The heater becomes
very hot and it will
burn your skin if you
touch it, so only have
the heater switched on
when it is inside the
metal block and leave
the heater inside the
block until it has
cooled. After removing
the heater from the
block, handle carefully,
do not touch the
element, and place on a
heat-resistant mat.
Explain why a temperature rise of about 10°C is more reliable
than one of 5°C or 20°C.
During heating, energy is lost to the surroundings. Describe
how this energy loss occurs.
Suggest how energy loss to the surroundings could be reduced.
What effect does the energy loss have on the measured values
of specific heat capacity compared to the actual values?
At a given temperature, the average kinetic energy of the atoms
in a metal is the same for all metals. Suggest why the different
metals have different specific heat capacities.
material
initial temp.
in °C
final temp.
in °C
brass
30
current in A
voltage in V
time in s
specific heat capacity
= (current × voltage × time)
÷ (1 kg × temperature rise)
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Physics TBA3
Activity A3.7
Aim
Materials required
In this experiment you will calculate the amount of work done
when a weight is lifted vertically in the Earth’s gravitational field.
This will help you to develop observational skills and practice
using the relationship between efficiency and work. You will
also understand the advantages and disadvantages of using a
ramp as a machine.
■
■
■
■
■
What to do
1
2
3
Write a plan for this experiment. Make a
list of the steps you are going to follow.
Include scientific knowledge in your plan
and try to use this to make a prediction.
Measure the energy input needed to raise a
load by lifting it vertically and by dragging
it up a slope for different heights of the
ramp.
Wooden board,
approximately 1m
long
1 kg mass
Metre rule
0–10 N forcemeter
Wooden blocks for
raising one end of the
ramp
ce s
Distan
Vertical
height h
1 Kg mass
Force meter
Complete the table of results at the bottom of the page.
1
2
3
4
5
6
Which requires more work, lifting the mass or dragging it up
the slope?
Explain why this method requires more work.
Does the mass gain more energy when it is lifted, or more
energy when it is dragged or the same amount of energy
whether it is lifted or dragged?
Explain why heavy objects are loaded into vans or lorries by
dragging them up a slope rather than by lifting them.
What is the disadvantage of dragging a heavy object up a slope
rather than lifting it?
What is the relationship between the efficiency of the ramp and
the steepness of the slope?
height of ramp,
h in m
force needed to lift
mass vertically
through height
h in N
work done in lifting
mass vertically in J
force required to
drag mass through
distance s up slope
in N
work done in
dragging mass up
slope in J
efficiency of ramp =
work done in lifting
mass ÷ work done in
dragging mass
0.10
0.20
0.30
0.40
0.50
31
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Physics TB1
Teachers’ and technicians’ notes 1.1
Aim
Materials required
This experiment enables students to study the
effect of connecting resistors in series.
Activity procedure
1
Students use a multimeter to measure the
resistance of two resistors on their own and
then connect them in series and measure the
resistance of the combination of resistors.
2
Pupils compare the individual values for two
resistors with the value when they are
connected in series and are expected to
discover what the relationship between the
values is.
3
There is an opportunity to extend the enquiry
to three resistors connected in series.
per
group
Digital multimeter
1
Crocodile clips
4
Clip component holders
2
Connecting leads
3
Resistors
see
per ( )
groups
below
Running the activity
A demonstration of the multimeter in use will be
very helpful.
Students may need help in interpreting the display
on the multimeter.
Multimeters
Other resources
Physics Book pp.4–9
Customisable worksheet on CD-ROM
Sc1 match
The choice of range for the multimeter will vary
from one manufacturer to another. Matching the
range of resistor value to the multimeter will be
necessary.
Choice of resistors
Planning
Not available
■
Any 0.5 W metal film resistors can be used.
Obtaining
available
■
Analysing
available
Values can be chosen to keep the value of the
combination below the maximum value
measurable.
Evaluating
available
■
The following selection from the E12 series is
suggested for different multimeter ranges.
■
Twenty of each of the values suggested will be
adequate for a group of 30 pupils.
Key skills match
Application of number
✓
Communication
✓
Multimeter range
1 kΩ
K10, K12, K15, K18, K22, K27,
K33, K39, K47
2 kΩ
K18, K22, K27, K33, K39, K47,
K56, K68, K82
ICT
Customising the student sheet
■
Removing the table allows access to skill O
but the skill level involved is low.
■
It will be necessary to change the instructions
regarding which scale on the multimeter to
use if the meter does not have a 2 kΩ scale.
■
Reference to either clip component holders or
crocodile clips can be deleted.
32
Resistor values
M
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Physics TB1
Teachers’ and technicians’ notes 1.3A
Current–voltage graph for a metallic conductor
Aim
Materials required
This experiment enables students to investigate
the relationship between voltage and current for a
metallic conductor.
Students use a circuit diagram to connect an
electrical circuit, tabulate results and process them
both numerically and graphically before drawing
conclusions from their results.
Activity procedure
1
Students connect a length of metallic
conductor into a circuit and measure current
through and voltage across the conductor.
2
The voltage is varied and the corresponding
values of current and voltage are recorded.
per
group
2 m length wire
1
Voltmeter
1
Ammeter
1
Connecting leads
5
Crocodile clips
2
30 cm ruler
1
per ( )
groups
Pupils shoud be aware of the safety warning.
Other resources
The use of constantan/eureka minimises the effect
of changes in temperature on the resistance of the
conductor.
Physics Book (pp.8–9)

Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Safety
Two metre lengths of 28 swg constantan will
remain cool to the touch when voltages below 16 V
are used, but very short lengths may get red hot.
Sample results
Key skills match
resistance (in Ω)
voltage (in V)
current (in A)
0
0
1
0.03
33
✓
2
0.06
33
Communication
✓
3
0.08
38
ICT
✓
4
0.11
36
5
0.14
36
6
0.16
38
■
7
0.19
37
8
0.22
36
9
0.24
38
10
0.27
37
11
0.3
37
12
0.33
36
The range of voltages and the number of
readings can be varied.
14
Voltage (V)
12
10
8
6
4
2
0
0
0.05 0.1
0.15 0.2
0.25 0.3
0.35
Current (A)
33
A
?
Physics TB1
Teachers’ and technicians’ notes 1.3B
Current–voltage graph for the filament of
a light bulb
Aim
the relationship between voltage and current for
the tungsten filament of a light bulb.
Pupils use a circuit diagram to connect an
electrical circuit, tabulate results and process them
both numerically and graphically before drawing
conclusions from their results.
Activity procedure
1
Materials required
per
group
Light bulb in holder
1
Voltmeter
1
Ammeter
1
Connecting leads
5
Power supply
1
2
per ( )
groups
Sample results
Students connect a light bulb into a circuit
and measure current through and voltage
across the filament.
current (in A)
0
0
1
0.61
1.64
2
0.81
2.47
3
0.98
3.06
4
1.13
3.54
5
1.26
3.97
6
1.40
4.29
7
1.50
4.67
8
1.61
4.97
9
1.71
5.26
10
1.81
5.52
11
1.90
5.79
Other resources
Physics Book (p.8–9)
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Key skills match
resistance (in Ω)
voltage (in V)
The voltage is varied and the corresponding
values of current and voltage are recorded.
14
✓
Communication
✓
ICT
✓
12
10
Voltage (V)
M
8
6
4
12 V 24 W light bulbs are suitable for this
experiment.
2
0
0
0.5
If dedicated holders are not available, an optical ray
box with bulb could be substituted.
1
1.5
2
2.5
Current (A)
 Safety
A light bulb will get hot enough to burn you. Keep
fingers away.
34
M
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Physics TB2
Aim
Materials required
per
group
the conditions needed to balance a metre rule
experiencing opposing moments.
Drilled metre rule
1
Short metal rod
1
The data collected have to be processed and lead to
an understanding of the principle of moments.
Boss
1
Giant paperclips
52
100 g slotted masses
2
Activity procedure
1
2
Students balance a metre rule using forces
provided by slotted masses suspended from
giant paperclips that are able to move along
the rule. The rule itself is pivoted at its
mid-point so its weight provides no turning
moment.
The sizes of the forces involved and the
distances from the pivot are noted and used to
discover that, within the limits of
experimental error W1 × d1 = W2 × d2.
Other resources
per ( )
groups
A demonstration of the procedure may be helpful.
It is important that pupils appreciate that the mass
hanger on its own has a weight of 1 N.
The suggested position for the boss on the stand
reduces the risk of the metre rule spinning
violently when unbalanced.
Steel rod with a diameter of 4 mm cut into 5 cm
lengths is suitable for making the short metal rods.
A hole should be drilled in the metre rule at the
50 cm mark using a twist drill 0.5 mm larger than
the diameter of the metal rod.
Giant paperclips are approximately 7.5 cm long and
1.5 cm wide. They slide easily over a metre rule.
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Students should find that the metre rule is
balanced when clockwise and anticlockwise
moments are the same. This can be expressed as
W1 × d1 = W2 × d2
Where there are two weights on one side, the sum
of the moments should balance the moment on the
other side
Key skills match
✓
Communication
✓
(W1 × d1) + (W2 × d2) = W3 × d3
ICT
■
Removing the table allows access to skill O
but the skill level involved is low.
35
M
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Physics TB2
Activity procedure
1
Materials required
Students run a model car down an inclined
plank starting it from different distances up
the plank.
2
The time is measured for the car to reach the
bottom of the plank. Students measure the
distance the car travels before coming to rest.
3
From these measurements students can work
out the speed of the car.
per
group
Wooden plank (1 m–1.5 m long)
1
Free-moving vehicle e,g. toy car, dynamics
trolley
1
Metre rule
1
Stopwatch
1
Wooden blocks to incline plank
several
Calculator
Other resources
1
Additional masses may be required for
extension work
Physics Book (pp.16–17).
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Pupils need to ensure that there is enough space at
the end of the plank for the car to run to standstill.
The same surface should be used for all
measurements.
Sample graph
✓
Communication
✓
ICT
Stopping distance, in m
2.2
Key skills match
■
■
This activity can provide useful practical work
for a wide range of abilities.
For lower abilities, restrict the activity to one
angle and provide a blank copy of the table of
results. You could also provide an Excel
spreadsheet where they input their results and
average times, average speeds, speeds at the
bottom and average distances are calculated.
For higher ability pupils, the activity can be
extended by getting them to alter the angle of
the plank. Alternatively, masses can be added
to the car. Then predictions can be made based
on f=ma. Now there are full opportunities for
POAE.
36
x
x
2.0
x
1.8
1.6
x
1.4
x
x
1.2
1.0
■
per ( )
groups
x
0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6
Answers
2
3
4
(a)
(b)
She thinks it will double the distance.
No it is greater than Kim thinks. Distance
is proportional to speed squared.
Measuring the time.
Repeat with more distances, especially 1.1 m/s
and above.
 Safety
Poorly supported planks may fall on toes and
fingers. Work on floor to avoid heavy dynamics
trolleys falling off benches. Use ‘catch boxes’ of, for
example, scrap polystyrene or foam rubber at the
end of the steeply inclined runways.
M
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Physics TB2
Sample results
Distance travelled
down slope in m
Time taken to travel down slope in s
1
2
3
Ave
Average
speed in
m/s
Speed at
bottom in
m/s
Stopping distance in m
1
2
3
Ave
0.30
0.78
0.85
0.78
0.80
0.38
0.76
1.02
1.00
1.04
1.02
0.40
0.84
0.91
0.93
0.89
0.45
0.90
1.21
1.23
1.23
1.22
0.50
0.97
1.00
0.97
0.98
0.51
1.02
1.39
1.40
1.41
1.40
0.60
1.12
1.03
1.10
1.08
0.56
1.11
1.60
1.56
1.58
1.58
0.70
1.18
1.19
1.21
1.19
0.59
1.18
1.84
1.80
1.79
1.81
0.80
1.28
1.25
1.31
1.28
0.63
1.25
2.07
2.02
2.00
2.03
0.90
1.37
1.33
1.33
1.34
0.67
1.34
2.18
2.21
2.20
2.20
37
M
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Physics TB2
Friction
Aim
Materials required
This experiment enables students to find the force
needed to move a block across a board. They then
find the relationship between the mass of the block
and the frictional force.
Activity procedure
1
Students pull a block of wood along across a
wooden board. The force required to pull the
block is found.
2
The block is loaded with weights and the force
required to pull it along is found.
3
As an additional activity, the area in contact
could be varied, the surface of the board could
be changed and a lubricant could be used.
per
group
Wooden block with screw eye
1
Wooden board
1
0–5 N forcemeter
1
Masses, 10 × 100 g
10
per ( )
groups
Access to balance
Sample results
Mass of block = 200 g
Total mass in g
Friction force in N
200
0.4
Other resources
400
0.8
600
1.2
800
1.6
1000
2.0
1200
2.4
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Material preparation
Evaluating
available
Wood blocks approximately 15 cm × 10 cm × 2 cm
with a screw eye fitted to one of the smallest faces.
The wooden board should be about 50–100 cm
long. Chipboard is a suitable material.
Key skills match
✓
Communication
✓
Sample graph
2.5
x
■
■
For lower ability pupils a table of results and a
blank grid with axes labelled and scales could
be provided.
Friction force, in N
ICT
x
2.0
x
1.5
x
1.0
x
0.5
x
0
For more able pupils an investigation could be
carried out to find how the area in contact
with the board affects frictional force.
0
200
400
600 800
Mass, in g
1000 1200
Answers
4
This activity provides good opportunities for
practical activity. The nature of the equipment
used makes repeat readings of little value.
5
38
Pulling the block at a steady speed and
measuring the force accurately with the
forcemeter.
The area of the block in contact with the
board and the nature of the surfaces.
M
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Physics TB2
Aim
Materials required
Students propel an empty margarine tub across the
floor and measure the distance travelled.
Selection of elastic bands
They are able to alter one factor, e.g. distance the
elastic band is pulled back. The legs of a laboratory
stool are suitable for forming the catapult to launch
the projectile. Slotted masses are used to alter the
weight of the projectile.
per
group
Forcemeter 0-10 N
1
Margarine tub
1
Slotted masses
1
Metre rule
Activity procedure
1
per ( )
groups
Sellotape
Set the scene with the students and let them
choose a factor to investigate.
Sc1 match
Full investigation with full Sc1 mark scheme.
Suggested marking criteria
Skill Area P: Planning
Planning
available
Obtaining
available
Analysing
available
Evaluating
available
The mark descriptions are designed to be hierarchical.
Candidates
Contextualised mark descriptions
2 marks
P.2a
Outline a simple procedure
Plans to change a suitable factor and measure the distance travelled by a
projectile.
4 marks
P.4a
Plan to collect evidence which will be
valid
Plans to change the number of elastic bands, or extension of a band, or mass
of the projectile and measure the distance travelled. Refers to controlling all
variables except the one under investigation to ensure a fair test.
P.4b
Plan the use of suitable equipment or
sources of evidence
Writes a list of or describes suitable equipment to use, e.g. elastic bands of
similar type and length, metre rule, force meter, projectile and associated
launching equipment such as retort stands or chair legs.
P.6a
Use scientific knowledge and
understanding to plan and
communicate a procedure, to identify
key factors to vary, control or take into
account, and to make a prediction
where appropriate
Uses and communicates clearly scientific knowledge to underpin the plan.
Identifies the factor to vary: a continuous variable such as extension of elastic
band, or mass of projectile.
Identifies explicitly the factors to control for the particular investigation.
Predicts that increasing the extension of the band or decreasing the mass of
the projectile increases the distance travelled because of the increased energy
transferred to the projectile or the lower friction force respectively.
P.6b
Decide a suitable extent and range of
evidence to be collected
Plans to use a range of at least five different values of the variable under
investigation to produce significant variations in the distance travelled by the
projectile.
P.8a
Use detailed scientific knowledge and
understanding to plan and
communicate an appropriate strategy,
taking into account the need to produce
precise and reliable evidence, and to
justify a prediction, when one has been
made
Uses and communicates clearly a suitably detailed and quantitative scientific
approach to predict the effect of changing the variable under investigation on
the distance travelled. For example, includes the ideas of potential energy,
kinetic energy, friction and uses equations such as
Energy transferred = (friction) force x distance travelled.
Due to the limited opportunity provided by the procedure to show precision and
skill, recognises the need to use a sampling technique with a large range of
extensions/masses and multiple repeats to ensure reliable data.
P.8b
Use relevant information from
preliminary work, where appropriate, to
inform the plan
Performs and reports preliminary practical work to select an appropriate range
of the variable under investigation to give meaningful results.
6 marks
8 marks
continued
쑺
39
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Physics TB2
Skill Area O: Obtaining evidence
Candidates
2 marks
O.2a
Collect some evidence using a simple
and safe procedure
Uses equipment safely and makes a single measurement of the distance
travelled when the number of elastic bands, or the extension of a band, or
mass of the projectile is changed.
4 marks
O.4a
Collect appropriate evidence which is
adequate for the activity
Uses a suitable range of five values of the extension or mass of projectile to
produce meaningful results of the distance travelled.
O.4b
Record the evidence
Records the measurements in any format.
O.6a
Collect sufficient systematic and
accurate evidence and repeat or check
where appropriate
Uses a suitable range of five values of the extension or mass of projectile to
produce meaningful results of the distance travelled. Repeats the
measurements so that an average can be determined.
O.6b
Record clearly and accurately the
evidence collected
Records results clearly in a tabular format.
Use a procedure with precision and
skill to obtain and record an
appropriate range of reliable evidence
Recognises that due to the nature of the investigation, measurements of
distance travelled needs to be recorded to the nearest cm only.
Due to the limited opportunity provided by the procedure to show precision
and skill, uses a sampling technique with a large range of extensions/masses
and multiple repeats to ensure reliable data. Differences between repeat
measurements are such as to enable a meaningful average to be calculated.
The accuracy and reliability of the data can be inferred from inspection of the
associated graph
6 marks
8 marks
O.8a
Heads columns correctly with appropriate units and records results with
acceptable and consistent number of significant figures.
Skill Area A: Analysing and considering evidence
Candidates:
2 marks
A.2a
State simply what is shown by the
evidence
States simply what has happened, e.g. the further the elastic band was pulled
back the further the projectile travelled.
4 marks
A.4a
Use simple diagrams, charts or graphs
as a basis for explaining the evidence
Plots a bar chart or simple graph of the distance travelled against extension,
mass or number of elastic bands.
A.4b
Identify trends and patterns in the
evidence
Uses the graph, bar chart or data table to identify a trend, e.g. as the mass of
the projectile increases the distance travelled decreases.
A.6a
Construct and use suitable diagrams,
charts, graphs (with lines of best fit,
where appropriate), or use numerical
methods, to process evidence for a
conclusion
Plots a graph of the distance travelled (average values) against mass or
extension. Points are plotted accurately with suitably labelled and scaled axes.
Line of best fit is drawn.
A.6b
Draw a conclusion consistent with the
evidence and explain it using scientific
knowledge and understanding
Draws a qualitative conclusion, which refers to the effect of mass or extension
on distance travelled. Explains effect using scientific knowledge and correct
terminology involving terms such as energy, force, and friction. For example,
the heavier the projectile the more friction acts against motion and the less
distance will be travelled.
A.8a
Use detailed scientific knowledge and
understanding to explain a valid
conclusion drawn from processed
evidence
Analyses the graph in a more quantitative way and uses a convincing
quantitative explanation based on suitable equations such as
Explain the extent to which the
conclusion supports the prediction, if
one has been made
Compares the results to the original prediction. Clearly tests such predictions as
‘doubling mass halves distance’ by using the data collected from the graph or
plotting distance against 1/mass.
6 marks
8 marks
A.8b
40
Energy = (friction) force x distance
M
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Physics TB2
Skill Area E: Evaluating
Candidates:
2 marks
E.2a
Make a relevant comment about the
procedure used or the evidence
obtained
Makes any relevant comment about the method used or the data collected.
4 marks
E.4a
Comment on the quality of the
evidence, identifying any anomalies
Comments on the accuracy of the results
e.g. from inspection of the graph all points were close to the best-fit curve;
due to the nature of the investigation, only appropriate to measure distances
to the nearest +/- 1 cm.
Recognises any anomalous results.
E.4b
Comment on the suitability of the
procedure and, where appropriate,
suggest changes to improve it
Comments on the procedure
e.g. projectile rotates/loses contact with the floor during movement; launch
procedure not always consistent; hard to ensure that the projectile always
moved in a straight line
Suggests improvements
e.g. repeat measurements over a greater range of values of extension or
mass; use a clamp system to release the projectile in a standardised way;
use ‘guide lanes’ to ensure linear movement.
E.6a
Consider critically the reliability of the
evidence and whether it is sufficient to
support the conclusion, accounting for
any anomalies
Comments on how close the repeated measurements were to each other
and whether sufficient to support the conclusion.
Refers to multiple sampling technique.
Careful explanation of why rotation/launch procedure can affect distance
travelled and produce anomalous results.
Careful consideration of, for example, the unreliability of measurements
when using low masses.
E.6b
Describe, in detail, further work to
provide additional relevant evidence
Depending on the conclusion made, describes in detail further work
e.g. investigate a different surface to see if there is a different quantitative
relationship between distance travelled and extension; use light gates to
measure the times taken to pass particular distances to produce a more
detailed profile of the motion involved.
6 marks
41
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Physics TB2
Aim
Material required
This experiment enables students to measure their
reaction time.
Half-metre rule
Students first check that they can interpret data
presented graphically.
Values obtained for reaction times in this activity
are used to calculate ‘thinking distances’ for
motor vehicles.
per
group
per ( )
groups
1
■
Students could be asked to comment on the
reliability of their measurements.
■
The way of ‘catching’ the rule could be varied.
Activity procedure
1
Students interpret data presented graphically.
2
Students carry out an experiment to measure
their reaction time when a ruler is dropped
without warning.
3
The values obtained are used to calculate the
distance travelled by a motor vehicle
travelling at different speeds while the driver
reacts to a hazard.
Students need to be confident that they can
interpret the graph
Answers
distance fallen by
rule (in cm)
time taken (in s)
5
0.10
10
0.14
18
0.19
28
0.23
Other resources
Speed
(in mph)
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Speed
(in m/s)
Distance
travelled (in m)
20
9
1.8 to 2.7
30
13
2.6 to 3.9
50
22
4.4 to 6.6
70
30
6 to 9
This is a poor task for the assessment of Sc1
Sample results
Key skills match
Typical values for reaction times for this method
are in the range 0.2 to 0.3 seconds.
✓
Communication
ICT
■
The values in the table for point 4 can be made
harder or easier to handle.
42
M
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Physics TB2
Teachers’ and technician’s notes 2.10A
Aim
Materials required
This experiment enables students to discover that
when a ball falls in a fluid there is a drag force
which opposes the motion of the ball and that
eventually the ball reaches a terminal velocity.
per
group
3
Measuring cylinder (500 cm )
per ( )
groups
1
500 cm3
Fresh motor oil
Small elastic bands
3
Two small steel ball bearings (one of
diameter 4 mm and one smaller)
Activity procedure
30 cm ruler
In this investigation the student finds out how the
diameter affects the terminal velocity.
1
Stopwatch
1
Magnet
1
Tissues
Other resources:
Propane 1,2,3trio(glycerol) is a useful alternative
and can be handled safely.
Sc1 match
Answers
1
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Distance between A and B and between B and
C is 10.0 cm.
Time from
A to B in s
Large
Key Skills match
✓
Communication
✓
10.5
10.7
10.6
available
10.4
Small
ICT
For less able students, a copy of the table can
be provided.
For more able students, a range of different sized
ball bearings could be provided and students could
devise a method of finding the diameter of each
ball. They could also investigate the relationship
between terminal velocity and diameter, (terminal
2
velocity is directly proportional to d ).
For less able students, a table of results could be
provided.
Materials preparation
Clean motor oil should be used. This should be
collected at the end of the experiment and re-used.
Propane 1,2,3triol(glycerol) is a useful alternative
and can be handled safely.
2
3
4
5
Av 10.4
14.2
15.0
14.6
14.5
Av 14.3
Average
velocity
from B to
C in cm/s
10.0
1.0
14.1
Time from
B to C in s
10.4
10.1
■
Average
velocity
from A to
B in cm/s
1.0
14.1
0.7
14.5
0.7
Shown in the table.
The time between A and B is the same as the
time between B and C (allowing for
experimental error).
The evidence based upon two sizes of ball
bearings is not enough. Other sizes of ball
bearings should be used.
Temperature changes may affect results.
Difficulty of accurate timings due to human
reaction times starting and stopping clock.
Longer tube would give greater times and
reduce errors.
Suggest using light gates/sensors to improve
timing.
 Safety
Avoid skin contact with motor oil. Use disposable
gloves or paper towel/tissue to handle oil-covered
ball-bearings. Do not let students pour oil into
sinks or drains. Tell them to wash hands after use.
43
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Physics TB2
Aim
investigation on the behaviour of a ping-pong
ball after practising the procedure with a
golf ball.
the behaviour of falling objects by gathering data to
plot velocity–time graphs for objects where the
ratio of gravitational force to resistive forces varies
significantly.
■
Students have an opportunity to show what they
know and understand about the effect of forces and
terminal velocity.
The data collected can be processed manually or by
using a spreadsheet and a linked graph-plotting
package.
A demonstration of the procedure may be helpful.
Activity procedure
1
Students allow balls of different weights to fall
under the influence of gravity and resistive
forces.
2
Students should be familiar with the use of ticker
timers.
If possible, the experiment could be carried out by
dropping a large sponge ball down a stair well for
two storeys.
Sample results
Ticker tape and timers are used to record the
position of the balls at 0.02 s intervals.
The separation of the marks produced is
measured and used to calculate the velocity of
the balls at 0.02 s intervals allowing graphs of
velocity against displacement to be plotted and
analysed.
6000
5000
Velocity in m/s
3
References to velocity and displacement can
be replaced by speed and distance for lower
ability students.
4000
3000
2000
1000
0
Other resources
0
0.1
0.2
0
0.2
0.4
Physics Book (pp.32–33, p.4)
0.3
0.4
Time in s
0.5
0.6
1
1.2
2500
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
✓
Communication
✓
ICT
✓
Removing references to a ping-pong ball
allows students to carry out a complete
44
2000
1500
1000
500
0
Key skills match
■
Velocity in m/s
Sc1 match
0.6
0.8
M
A
?
Physics TB2
Aim
Materials required
This experiment enables students to use
datalogging to compare rates of cooling from
various types of container under identical
conditions.
Activity procedure
250 cm3 measuring cylinder
1
Waterproof marker
1
Polystyrene cups and a lid
2
per ( )
groups
Access to kettle for hot water
1
Students investigate speed of cooling of a
vessel with and without a lid.
2
Students work out cooling rates and interpret
their results using computer and datalogging
software.
Other resources
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Key skills match
Communication
✓
ICT
per
group
3
Standard 200 cm expanded polystyrene cups are very
suitable for this experiment, but some thin plastic
cups collapse when very hot water is poured into
them. Alternative cups should be checked by pouring
boiling water into a single cup which is in a sink.
Care should be taken because of the scald risk with
the water. Pouring from a kettle is safer than
having beakers and Bunsen burners. Cups should
be supported, e.g. with a wide clamp, so that they
cannot fall over.
It is recommended that two temperature sensors
are used together for swifter comparison, although
it can be done quite successfully using one
sequentially for each vessel. The analysis of cooling
rates over given temperature intervals avoids the
Temperature sensors and interface
2
Computer and datalogging software
Access to other cups, metal calorimeters
and vacuum flasks (for extension work)
need for each to start at the same temperature
(which is rarely exact even with two sensors). The
datalogging can be part of a class practical with
some students carrying out the practical using
thermometers and stopclocks in the usual way. If
you have access to an interactive whiteboard or
projection system, students can monitor progress
on the large screen at a glance from their
workstation. This is the best way to present the
experiment as a demonstration if the intent is to
focus on the data analysis aspect of the work.
Students should be given copies of the computer
graph output for analysis but may also be able to
input their own data (taken in the normal way with
thermometers) so that it can be presented in the same
format. In this event, they should be encouraged to
take temperature readings as frequently as possible to
get a large number of data points.
Normally it is sufficient to collect data for 10–15
mins but it may be useful to let some experiments
carry on longer to reinforce the point to less able
students that the cooling stops when the vessel
reaches room temperature and avoid the
misconception that it cools to the lowest point
available on the graph scale (usually zero).
Data processing
Typically, a lidded cup will cool some two and a
half to three times slower than an open cup
between 80 and 75°C so the difference is quite
easily measurable over a short period of time.
Students could look at the possibility of using bar
charts to show how the rate of cooling changes as
the temperature range nears room temperature.
There is a good opportunity here to extend the use
of ICT to include spreadsheets.
45
M
A
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Physics TB3
Aim
Materials required
the behaviour of a ray of light when it is reflected
by a plane mirror.
Students are able to draw conclusions from their
observations and comment on the reliability of the
evidence gathered.
Extension material allows students to be
introduced to the use of plane mirrors in a
periscope.
Activity procedure
1
Students shine rays of light onto a plane
mirror and draw the path of the rays on paper.
2
Angles of incidence and reflection can be
measured and compared.
per
group
Plane mirror
1
Mirror holder
1
Ray box
1
Single slit
1
Power supply
1
Protractor
1
Plain paper
1
Pencil
1
per ( )
groups
A means of providing partial blackout will be
needed.
Other resources
Either plastic mirrors cut from a large sheet or
small plane mirrors can be used.
Bulldog clips can be used as an alternative to
commercially available mirror holders.
Sc1 match
Sample results
Planning
Not available
angle i
angle r
Obtaining
available
23°
24°
Analysing
available
32°
31°
Evaluating
available
46°
46°
57°
55°
68°
70°
79°
81°
Key skills match
✓
Communication
✓
ICT
■
Point 6 in the ‘what to do’ section can be
changed to remove reference to either plastic
or glass mirrors.
■
The number of angles to be used can be varied.
■
Extension work can be removed.
46
M
A
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Physics TB3
Teachers’ and technicians’ notes 3.5A
Aim
Materials required
the behaviour of a ray of light when it passes
through a perspex block.
Students are able to draw conclusions from their
observations and comment on the reliability of the
evidence gathered.
As an extension, students could complete Activity
3.5B and use a spreadsheet to investigate the
relationship between i and r.
per
group
Perspex block
1
Ray box
1
Single slit
1
Power supply
1
Protractor
1
Plain paper
1
Pencil and ruler
1
per ( )
groups
Activity procedure
1
Students shine rays of light onto a perspex
block and draw the path of the rays on paper.
2
Angles of incidence and refraction can be
measured and compared.
Other resources
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Sample results
angle i
angle r
10°
7.5°
20°
15.0°
40°
29.5°
50°
36.0°
60°
41.5°
70°
46.5°
Key skills match
✓
Communication
✓
ICT
A means of providing partial blackout will be
needed.
47
M
A
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Physics TB3
Aim
Materials required
This experiment enables students to collect angles
of incidence and refraction for a number of light
rays and then use a spreadsheet to find the best
mathematical relationship between them.
Activity procedure
1
Students measure angles of incidence and
refraction using a raybox and glass block.
2
Students use a spreadsheet to find a relationship between angles of incidence and refraction.
per
group
Glass or plastic semi-circular block
1
Sheet of A3 paper
1
Raybox with narrow slit
1
Protractor
1
Ruler
1
Sharp pencil
1
per ( )
groups
Access to computer with spreadsheet
package such as EXCEL
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
The ray box should have as narrow a slit as possible
to improve accuracy, students should be
encouraged to use very sharp pencils for the
marking out and try to achieve a reading accuracy
of half a degree from the protractor.
Although a minimum of six values of incidence
angle are suggested (10° intervals) it is reasonable to
expect most students to do more (e.g. 5° intervals)
Key skills match
Spreadsheet work
Communication
✓
ICT
Students should have had some previous
experience with spreadsheets.
Glass or plastic blocks are equally suitable. It may
be useful to have the centre of the flat side marked
with a small gap in black tape or marker pen to
improve the narrowness of the beam (see diagram).
Approx 1 cm
blacked-out
It is advisable to prepare a suitable spreadsheet ready
for students to access. For the weakest students, the
headings and functions could be in place as shown
for the common spreadsheet EXCEL. The functions
shown in row 2 need to be copied down the column
for enough rows to accommodate the likely data
sets. Similarly, the number of decimal places should
be specified in advance.
More able students could be left to insert their own
headings and functions starting with a basic
template to insert angle data.
Centre left clear
Discussion may be needed to establish the best
relationship (Snell’s sine ratio) and use of
correlation functions could be examined.
 Safety
The exercise can be purely data-handling if
students are supplied with information for
materials of different refractive indices.
Do not knock glass blocks against each other. Bits
of glass may fly off.
A
B
1
Angle (i)
Angle (r)
TAN (i)
TAN (r)
SIN (i)
2
10
7.7
=TAN (A2
*PI()/180)
=TAN (B2
*PI()/180)
=SIN (A2
*PI()/180)
48
C
D
E
F
G
H
SIN (r)
COS (i)
COS (r)
=SIN (B2
*PI()/180)
=COS (A2
*PI()/180)
=COS (B2
*PI()/180)
M
A
?
Physics TB3
Answers
1–3 Having worked out a relationship, students
4
could be encouraged to continue to use the
spreadsheet to look at the effect of errors. For
example, what difference does it make to the
slope of the line (proportionality constant/
refractive index) if there is a 1° error in reading
the angles of refraction? Students could add (or
subtract) 1° from each angle (r) and replot.
Students could research the significance of
high refractive index lenses (thinner for the
same correction power), for example, by using
web sites for high street opticians.
Refraction data
The following can be used as source data for an
investigation of the refractive index of unknown
materials.
This might be used for Analysis.
Material A: Refractive Index 1.3
Angle of incidence °
10
15
20
25
30
35
40
45
50
55
60
65
70
Angle of refraction °
7.5
11.5
15.0
19.0
22.5
26.0
29.5
33.0
36.0
39.0
41.5
44.0
46.5
Material B: Refractive Index 1.5
10
15
20
25
30
35
40
45
50
55
60
65
70
6.5
10.0
13.0
16.5
19.5
22.5
25.5
28.0
30.5
33.0
35.0
37.0
38.5
Material C: Refractive Index 1.7
10
15
20
25
30
35
40
45
50
55
60
65
70
6.0
8.5
11.5
14.5
17.0
19.5
22.0
24.5
27.0
29.0
30.5
32.0
33.5
49
M
A
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Physics TB4
Aim
Materials required
This experiment enables students to determine
that the speed of electromagnetic waves changes
when they pass from one material into another and
that this is called refraction.
Students discover that the change in speed may
result in a change in direction and that the amount
by which the direction changes depends on the
wavelength and frequency of the waves.
per
group
Power supply
1
12 V 24 W lamp in holder
1
Slit to produce a narrow beam
1
Isosceles prism
1
White screen which will stand vertically
1
per ( )
groups
detected beyond the red and blue parts of the
visible spectrum.
Activity procedure:
1
Students direct a narrow beam of white light
from a source on to one face of an isosceles
triangular prism and place a vertical white
screen in a suitable position to detect the light
that leaves the opposite face of the prism.
■
2
Students adjust the position of the prism to
obtain the best spectrum and then observe and
record the appearance of the spectrum.
Other resources
Questions 4 and 5 should be removed for low
achievers as they will not understand the
wavelengths and frequencies given in standard
index form.
Students need to be shown how to position the
prism and the screen. They need to be reminded
how to connect the white light source to the power
supply and of the correct voltage setting.
Answers
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
High achievers should use an LDR connected
to a resistance meter to detect the
electromagnetic radiation within and either
side of the visible spectrum. They should use
secondary sources to identify the radiations
50
6
blue
7
At the faces of the prism.
change in speed.
✓
ICT
■
red, orange, yellow, green, turquoise (cyan),
blue.
1 The speed decreases.
2 blue
3 red
4 decreases
5(i) red
5(ii) blue
6 The longer the wavelength, the smaller the
Key skills match:
Communication
5
M
?
A
Physics TB4
Teachers’ and technicians’ notes 4.6–4.8
Aim
ICT required per group
This exercise enables students to search and gather
data off the internet from a variety of sites and to
use this data in an ICT context to construct a
suitable presentation.
Computer with:
–
–
–
Key skills match
–
–
–
internet connection
word processor
spreadsheet
desktop publisher
presentation package, e.g. Powerpoint
access to colour printer
Communication
ICT
✓
Once students are clear about the task, in the
interests of efficient time management it is worth
letting them spend a few minutes choosing suitable
search phrases before releasing them onto the
internet. Linked phrases such as ‘earthquake
statistics uk’ are usually good enough to narrow
down the search and get to a relevant web site.
The various seismic organisations are highly
interlinked so that once one is found, other
relevant ones are easily to hand. Photographs of
earthquake damage can be found on some sites, but
if there has been a recent big earthquake, television
news sites are a good source of visual material.
Unless funds are unlimited, it is advisable to set
ground rules about what can be printed and when it
should be done. Many students are happy to carry
on the activity at home.
You may wish to split the task between different
groups of students and co-ordinate their work in a
display. One strategy might be to split the world
into different areas and get each group to report on
what has been happening in their area. Another
might be to let one group of students prepare a
daily report which is published on a convenient
noticeboard. Students often suggest their own
variations, so be prepared to be flexible as to the
outcomes. Some American sites will allow you to
set up a search which can be left on the server for
about a week, constantly being updated. Some sites
also provide simulations for students to work
through. Although not always relevant to the task,
they can be useful in reinforcing important
concepts.
Some useful sites to get you started
Site
Comment
www.neic.cr.usgs.gov/neis
US national earthquake information centre
quake.geo.berkeley.edu/cnss
Berkeley Institute data bank
www.gsrg.nmh.ac.uk
UK National Seismological Archive
www.iris.washington.edu
Incorporated Research Institute for Seismology
vcourseware5.calstatela.edu
Simulation to locate quakes and calculate magnitude
www.ceri.memphis.edu
Centre for earthquake research and information
seismo.ethz.ch/seismosurf
Extensive lists and links
www.geo.ed.ac.uk/quakes/quakes.html
Edinburgh University earthquake locator
51
M
A
?
Physics TB5
demonstration
Materials required
Aim
for demonstration
This experiment enables students to observe that
radioactive emissions occur when unstable nuclei
change to a more stable state.
They will discover that there are three main types
of radioactive emission, known as alpha, beta and
gamma and that these radiations are distinguished
in terms of their penetration and their ability to
cause ionisation.
■
■
■
■
■
Alpha, beta and gamma sources and
suitable holder
Tongs for handling the sources
Detector, e.g. Geiger-Müller tube
counter
A range of thicknesses of aluminium foil
and lead
Students will discover that there is background
radiation from the ground, the atmosphere, the
food that we eat, buildings and medical and
industrial uses of radioactive materials.
 Safety
Activity procedure
Teachers should observe the following points:
1
2
3
4
Demonstrate the existence of background
radiation and obtain a value for the average
background count. Relate background
radiation to the various sources responsible.
Using an alpha source, students measure and
record the total count in one minute using:
(a) no absorber; (b) a 5 cm air gap as absorber;
and (c) a 3 mm thickness of aluminium as an
absorber.
Using a beta source, students measure and
(c) a 3 mm thickness of aluminium as an
absorber; and (d) a 2 mm thickness of lead as
an absorber.
Using a gamma source, students measure and
(c) a 3 mm thickness of aluminium as an
absorber; (d) a 2 mm thickness of lead as an
absorber; and (e) a 2 cm thickness of lead as an
absorber.
Other resources
Do not allow students access to any source. Check
for possible theft.
1
2
3
4
Key skills match
✓
Communication
✓
■
Removing the outline table of results will
make it useful for Sc1 Obtaining Evidence
skill.
■
High achievers should take sufficient
measurements to enable them to plot a graph
of count rate against thickness for the
aluminium absorber. They can use the graph
to estimate the thickness of aluminium
required to reduce the count rate by one half.
■
Low achievers should compare the
comparative dangers to users of radioactive
materials in terms of the penetration powers
only.
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
52
Do not handle any radioactive materials
directly: always use tongs or a source handling
tool.
Do not point radioactive materials at any
person, i.e. the metal gauze end of a sealed
source.
No student should be closer than 2 m to
radioactive materials.
The radioactive sources should only be
removed from the secure store when they are
needed and returned to that store as soon as
the experiments are completed.
M
A
?
Physics TB5
Teachers who have been trained to teach secondary
science are qualified to work with these sealed
sources. However, if the teacher is unfamiliar with
the activity there must be in-house training
organised by the head of department utilising those
who do have the appropriate skills. Where students
are under 16 years of age the activity must only be
a teacher demonstration.
Answers
1
2
3
4
5
6
Alpha, it had the greatest count rate.
Alpha.
The radiation is totally absorbed by a small air
gap, so it would not penetrate the plastic
casing of a smoke alarm.
Yes – even though the count rate with a 5 cm
air gap may be slightly higher than with no
absorber, the difference is accounted for by the
random variability in background radiation.
The radiation spreads out as it leaves the sources,
so less enters the window of the G-M tube.
Any two from:
■ stay at least 2 m away from a radioactive
material
■
never handle a radioactive material
directly, always use tongs
■
do not point a radioactive source towards
any person.
Sample results
source
absorber
number of counts in 1 minute
none
42
alpha
none
325
5 cm air
44
3 mm aluminium
39
none
255
beta
gamma
5 cm air
126
3 mm aluminium
41
2 mm lead
44
none
164
5 cm air
84
3 mm aluminium
66
2 mm lead
62
2 cm lead
51
53
M
A
?
Physics TB5
Aim
Materials required
per
group
This experiment teaches students that radioactive
decay is a random process and that decay of an
individual nucleus cannot be predicted.
computer
1
random number generator programme
1
Using a random number generator students
simulate radioactive decay and find a half-life.
access to printer
or
small cubes with one face painted
Activity procedure
1
Students generate random numbers from a
computer.
2
Students process the numbers and find a
half-life.
3
Students discover that large numbers are
required to get a valid half-life.
Other resources
per ( )
groups
240
This activity could be carried out with a large
number of cubes with one face painted. After each
throw every cube with the painted face pointing
upwards is removed. The remaining cubes are
thrown again.
Using a random number generator speeds up the
process. It also enables different groups to have
different number ranges, e.g. 1–6, 1–7, 1–8 etc. this
generates different ‘half-lives’.
Materials preparation
Sci match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
A number of random number generator
programmes can be downloaded from the Internet.
One example is http://segobit.virtalave.
net/rng.htm.
The alternative method uses a large number of
cubes with one face painted.
Sample results
Key skills match
Number generated
Number of throws
240
0
196
1
173
2
131
3
Customising the student sheet:
115
4
■
For able students no help needs to be given.
101
5
■
For less able students a copy of a blank table
and a grid with axes and scales could be
provided.
84
6
67
7
55
8
43
9
39
10
33
11
28
12
✓
Communication
✓
ICT
A number of groups of students are able to use a
single computer. They go to the computer to
generate numbers and then move away to process
them.
54
M
A
?
Physics TB5
Number of undecayed cubes
250
200
150
100
50
0
0
2
4
6
8
10
12
Number of throws
Answers
2
3
4
5
Place the material close to a Geiger-Muller
tube connected to a counter or ratemeter or
computer interface. Record the reading at
intervals.
It is a curve with a decreasing slope or
gradient.
Depends on students results. Using sample
results the half-life is about four throws.
Greater precision can be achieved by using a
larger number of random numbers at the start.
55
M
A
?
Physics TB7
electric charge and current: Teacher
demonstration
Aim
In this experiment students will learn that a flow
of electric charge is an electric current and that the
greater the rate of flow of charge, the greater the
electric current.
They will discover that the rate of flow of charge
can be increased by putting the charged plates
closer together and that the rate of flow of charge
can be decreased by putting the charged plates
further apart.
Activity procedure
1
Arrange the apparatus as shown in the
diagram.
2
Connect the dome of the van de Graaff
generator to one of the metal plates.
3
Connect the other plate to the galvanometer
and then to the earth connection on the van de
Graaff generator.
4
Switch on the van de Graaff generator.
5
Observe the motion of the ping-pong ball.
6
Observe the galvanometer.
7
Repeat for different plate separations.
Materials required for
demonstration
van de Graaff generator
Two metal plates
■ Ping-pong ball coated in graphite or conducting
paint, suspended by a nylon thread from a
wooden clamp stand
■ Sensitive galvanometer such as an Edspot
■ Connecting leads
All the above to be connected as shown in the
diagram on the Student Sheet.
■
■
 Safety
1
2
3
4
Other resources
2
3
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Key skills match
4
Communication
5
✓
ICT
Answers
1
The ping-pong ball carries charge from one
plate to the other, completing the circuit. This
56
High voltage. Discuss the dangers and
precautions necessary.
Do not touch the apparatus once the van de
Graaff generator is switched on.
Check that the dome and plates are not
charged before touching the apparatus at the
end of the experiment.
Keep students at a distance of 1.5–2.0 m.
means that charge flows around the circuit
and a current is indicated by the galvanometer.
++ –
When the ball touches the positive plate it
becomes positively charged. Like charges repel
so it moves away and is attracted towards the
negative plate.
On touching the negative plate the ball gains
electrons and becomes negatively charged.
Like charges repel so the ball now moves
towards the positive plate and the process is
repeated.
(a) moves faster
(b) increases
(a) When there is a smaller distance between
the plates the forces of attraction are
stronger so the ball moves more quickly.
(b) Since the ball moves faster charge is
transferred more rapidly from one plate to
the other – the rate of flow of charge is
greater. Current is equal to the rate of
flow of charge so the current increases.
M
A
?
Physics TB8
Aim
Materials required
In this experiment students find that the speed of a
motor using data from a light sensor and correlate
this with electrical readings using a spreadsheet.
Computer with datalogging software and
interface
1
Printer
1
Light sensor and light unit
1
Ammeter
1
Activity procedure
per
group
1
Students obtain data from a light sensor.
2
Students calculate the speed of a motor and
plot this against current, voltage and power
consumption.
Voltmeter
1
Variable power supply
1
The values obtained are analysed.
Electric motor fitted with flywheel
1
Suitable leads
1
3
Other resources
Access to a spreadsheet such as Excel
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Key skills match
Communication
ICT
per ( )
groups
✓
The motor should be the
Flywheel
Slit
type which has a
removable flywheel, such
as one from a Meccano
kit. Lego motors may also
Motor
be suitable. The flywheel
needs to have a slit which is fairly narrow in order to
produce fine spikes on the trace.
Current and voltage sensors could replace the
ammeter and voltmeter, but as these should not
change during a run, there is little to be gained by
using them.
If the light sensor needs calibrating, set it to zero
with the power off and 100% with the power on.
A 6 V or 12 V torch bulb is adequate for the light
unit. The presence of cardboard tubes on the sensor
and the light unit will cut out ambient light and
give clearer results, but the experiment can be
carried out without them in place.
Students should start at the minimum voltage
which will get the motor turning and use this to
decide suitable increments up to the maximum
rating. If there is not a continuously variable power
supply available, a suitable rheostat placed in series
with the motor will give an adequate voltage range.
To investigate the effect of
load, the easiest way is to
change the type of flywheel.
Identical diameter flywheels
made from card, plastic, wood
and different metals can be
used. Alternatively, lead foil
can be attached symmetrically
to add weight but keep
Light
the wheel balanced.
Students may suggest
that the motor is
turned and used to
raise known loads in
a vertical plane. This
is feasible provided
the motor will accept
a suitable spindle.
Lead foil
unit
Sensor
Motor
Weights
Variations
If there is a gearbox available for the motor, students
could look at the speed related to gear ratio and load.
Motors from different sources, e.g. model trains
and racing cars could be compared.
 Safety
High speed spinning discs are an obvious hazard.
Warn students of this.
57
M
A
?
Physics TB8
Teacher’s guide
Aim
Materials required
This experiment enables students to observe the
form of the induced emf in a coil as a magnet falls
past it, and to use datalogging to measure the speed
of the magnet and relate it to the emf.
per
group
per ( )
groups
Computer with appropriate datalogging
software and interface
Voltage sensor
Pair of light gates
Activity procedure
1
Students obtain data for variation in induced
voltage with speed of a moving magnet.
2
Students analyse results and display them
graphically (with possible use of Excel
spreadsheet).
Coil unit(s) – see below
Guide tube: glass or plastic 1.5m long,
30mm diameter
Small cylindrical magnet
Foam rubber
Other resources
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Key skills match
from a cardboard tube of appropriate diameter for
the guide tube being used. Connections can be
made simply with 4 mm plugs. If the unit is
mounted into a small plastic box, it will be more
durable. Coils from demountable transformers may
also be suitable as they have the advantage of high
numbers of turns but the disadvantage of having
square central holes which may not fit the guide
tube. Cylindrical magnets about 2 cm long are
suitable, and the stronger they are the better. If the
voltage sensor is not capable of reading negative
voltages, one solution is to offset the voltage using
the coil as part of a potential divider as shown.
To voltage sensor
+V
To voltage sensor
Coil
Communication
✓
ICT
OV
Resistor
(100R)
This experiment affords a useful example of using
two sensors in parallel and using the power of the
computer software to process the data. It may be
that the datalogging software is capable of
displaying derived speed values against induced
voltages, so avoiding the need to use a
supplementary spreadsheet program such as
‘Excel’. Some students will need to be given
specific instructions as to how to achieve this, but
more able ones could be allowed to do their own
program setting.
A satisfactory coil can be made from 250–300 turns
of 28 swg enamelled copper wire wound in a
narrow pattern around a former, manufactured
58
+SV
The experiments are quick to do and many
repetitions are possible within a normal lesson
span. One possible strategy is to allow all students
to take turns in small groups and pool the data.
Students could deliberately accelerate the magnet
down the tube instead of letting it fall under
gravity in order to obtain a larger range of speeds.
If light gates are not available, an alternative is to
vary the drop height. The magnet will be
accelerated to different speeds but they will not be
known. An estimate could be obtained using
standard motion equations, otherwise induced emf
can be related simply to the height.
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Physics TB8
Aim
Materials required
This experiment teaches students that a voltage is
induced when the magnetic field through a conductor
changes and that an induced current passes when a
voltage is induced in a complete circuit.
Students learn that the size of the induced voltage
depends on the rate at which the magnetic field
changes and that reversing the change of the magnetic
field reverses the direction of the induced voltage.
Activity procedure
1
2
Students wind a coil of 2–3 cm diameter and
15–20 turns, this is connected to a sensitive
ammeter which can detect currents in either
direction.
Students compare the ammeter deflection
when:
the N pole of a strong bar magnet is moved
slowly towards one end of the coil
the N pole of the magnet is moved quickly
towards the same end of the coil
per
group
1 metre length of single strand wire
2
Sensitive ammeter
1
Strong bar magnet
1
One pair of c-cores
1
1.5 V d.c. cell in holder
1
Switch
1
per ( )
groups
Connecting leads and crocodile clips as
necessary
1
Key skills match
✓
Communication
ICT
the magnet is held stationary inside the coil
the S pole of the magnet is moved towards the
same end of the coil.
3
4
Students then wind two separate coils of
15–20 turns onto iron c-cores; one coil (the
primary) is connected to a 1.5V cell through a
switch. The other coil is connected to a
sensitive ammeter.
Students compare the ammeter deflection
when:
Removing the outline table of results will make it
useful for Sc1 Obtaining Evidence skill.
High achievers should estimate and record the size
of the induced currents.
Low achievers will benefit from having the effects
demonstrated using a many-turn coil and a
datalogger to record the induced voltage.
the current in the primary coil is switched on
the current in the primary coil remains on
the current in the primary coil is switched off.
Other resources
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Students need to be made aware that they are
observing very small induced currents. They may
need to be shown how to zero the ammeter so that
positive and negative current values are readily
observed. It should be emphasised that all the turns
on each coil of wire should be wound in the same
direction.
continued
쑺
59
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Physics TB8
Sample results
Action
Ammeter indication
N pole moved slowly towards
coil
small positive pulse of current
N pole moved rapidly towards
coil
larger positive pulse of current
Magnet held stationary inside
coil
no current
S pole moved towards coil
negative pulse of current
Current in primary coil
switched on
positive pulse of current
Current in primary coil remains
on
no current
Current in primary coil
switched off
negative pulse of current
Answers
1
2
3
4
5
6
7
The faster the speed of movement, the greater
the reading on the ammeter.
Reverse the direction of movement of the
magnet; reverse the polarity of the magnet
(reversing the connections to the coil or the
direction of winding the coil are also
acceptable answers).
The magnetic field through the coil is not
changing.
The primary coil becomes an electromagnet,
its changing magnetic field passes through the
secondary coil.
As there is a steady current passing, the
magnetic field in the secondary coil is not
changing.
The magnetic field is now collapsing rather
than growing, so the change in the magnetic
field is opposite to when the current is
switched on.
An alternating current.
60
60
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Physics TB8
Aim
Materials required
This experiment will demonstrate to students that
a voltage is induced in a conductor when the
magnetic field through it changes.
2-metre lengths of single strand insulated
wire
2
Westminster power pack
1
Iron c-cores
2
2.5 V lamp in holder
1
Students will discover that a transformer consists of
two separate coils of wire wound on an iron core
and that a changing current in one coil (the primary)
produces a changing magnetic field in the other coil
(the secondary), causing an induced voltage.
Students will learn that a transformer can change
the size of an alternating voltage.
Activity procedure
per
group
per ( )
groups
Screwdriver
■
For low achievers, the action of the
transformer with both a d.c. input and an a.c.
input should first be demonstrated.
1
Students wind two separate 15- turn coils of
wire onto c-cores.
2
One coil (the secondary) is connected to a
lamp, the brightness of which gives an
indication of the size of the induced voltage.
3
Students connect a d.c. source to the primary
coil and note that the lamp does not light.
They then replace this with a low voltage a.c.
source and use the brightness of the lamp as a
reference for future experiments.
4
Students then change the numbers of turns of
wire on the secondary coil and note the
brightness of the lamp.
It is important that normal laboratory power
supplies are not used as they could be damaged.
If students join wires by twisting together the bared
ends, the joins must be insulated with tape and
students must be warned never to use this
procedure with mains electricity.
Sample results
Other resources
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Key skills match
Communication
✓
Customising the pupil sheet
■
Removing the outline table of results will make
it useful for Sc1 Obtaining Evidence skill.
■
High achievers could predict and investigate
the effect of changing the numbers of turns on
the primary coil, while keeping the number of
turns on the secondary coil the same.
Number of
primary
turns
Number of
secondary
turns
Lamp brightness
(off, dim, normal
or bright)
1.5 V d.c.
15
15
off
2.0 V a.c.
15
15
normal
2.0 V a.c.
15
10
dim
2.0 V a.c.
15
20
slightly brighter than
normal
2.0 V a.c.
15
25
bright
2.0 V a.c.
15
30
very bright
Answers
2
ICT
Input
(primary)
voltage
3
4
5
6
The magnetic field does not change when a
steady current passes. There is only a momentary
change when the current is switched on.
The magnetic field through the secondary coil
is continually changing.
There are fewer turns on the secondary than
on the primary.
There are more turns on the secondary than on
the primary.
(a) step-up.
(b) step-down.
61
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Physics TBA1
Teachers’ and technicians’ notes A1.1–A1.3
Logic circuits using AND, OR and NOT gates
Aim
Materials required
Students will learn how to set up logic circuits
using AND, OR and NOT gates and how to verify
the output signal for various inputs.
per
group
per ( )
groups
Low voltage (5 V) power supply
AND, OR and NOT gates – at least one of
each
Activity procedure
1
Students set up logic circuits and complete
truth tables.
2
Students discover that an AND gate gives a
high (logic 1) output only when both inputs
are high, an OR gate gives a high output when
either or both the inputs are high, and a NOT
gate acts as an inverter.
3
Students draw up truth tables to summarise
the behaviour of a logic gate.
4
Higher Tier students show that a NAND gate
inverts the output of an AND gate and a NOR
gate inverts the output of an OR gate.
Minimum of two input sensors, chosen from
light, temperature, moisture sensors
Suitable output, such as LED, lamp, buzzer
connecting leads
(H) NAND and NOR gates – at least one of
each
Extra gates and input sensors will be
required if some students go on to combine
logic gates
Note Teachers may wish to customise the pupil sheet to suit the
electronics system available.
Answers
Other resources
Manual provided by manufacturer of electronics
equipment.
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Key skills match
Communication
✓
ICT
This may need to be adapted depending on the
electronics system available.

Safety
Hazards are minimal with LV supply but students
using incorrect power settings may ‘blow’
components.
If in doubt the teacher should check a student’s
circuit before switching on the power supply.
62
1
AND gate truth table 0 0 0 1
OR gate truth table 0 1 1 1
NOT gate truth table 1 0 (for (i) and (ii))
2(b) Suggested practical applications:
AND
(i) To operate a washing machine or spin
dryer only if the door is shut.
(ii) To open a greenhouse window if it is hot
during the day.
OR
(i) To switch on the internal light in a car if
either driver’s or passenger’s door is open.
(ii) To switch on the central heating boiler if
the thermostat in the living room or
kitchen falls below a certain temperature.
NOT
to reverse the output of a sensor to give
the required response; e.g. so that the
output of a light sensor becomes high in
the dark and so a light is switched on.
2(c) Truth tables will depend on the combinations
of logic gates selected.
(H) level
1 Truth table for both is 1 1 1 0
2 Truth table for both is 1 0 0 0
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Physics TBA3
Teachers’ and technicians’ notes A3.6
Aim
Materials required
This experiment teaches students that the energy
required to raise the temperature of 1 kg of
material by 1°C or 1 K is called the specific heat
capacity and is measured in J/kgK or J/kg °C.
Students learn that the energy transfer from
electricity to a circuit component is calculated using
energy transfer = current × voltage × time = IVt.
Activity procedure
1
2
Students record the initial temperature of a
1kg metal block.
Students switch on the immersion heater until
the temperature has risen by about 10°C and
record the current, voltage and time for which
the heater is switched on.
3
Students record the maximum temperature
reached after the heater has been switched off
– not the temperature when the heater is
switched off.
4
The procedure is repeated for other metals.
per
group
per ( )
groups
1 kg blocks of aluminium, iron, brass and
copper
Stopwatch
1
Standard laboratory thermometer
1
12 V power supply
1
0–5 A ammeter
1
0–15 V voltmeter
1
12 V, 24 W immersion heater
1
the number of atoms in 1 kg of material for
the metals which are elements.
■
For low achievers, the activity can be
simplified by using a joulemeter to measure
the energy input – but note that these meters
require the use of an alternating voltage
supply.
Other resources
Physics Book (p 198–199).
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
A heat-resistant mat should be used underneath
the metal blocks. If time is short, different groups
can experiment with the different metal blocks and
pool results. Emphasise the dangers of handling the
heaters – there is no way of telling whether a
heater is hot or cold.
Groups of students may share metal blocks.

Safety
The heaters can burn the skin if allowed to get too
hot. When not in use, they should be left inside the
blocks or placed on a heat-resistant mat.
Key skills match
✓
Communication
✓
ICT
Beware of mercury from a broken thermometer
being left inside the hole in the block, with the
broken glass.
Answers
1
■
make it useful for Sc1 Obtaining Evidence.
■
High achievers should investigate the
relationship between the energy required and
2
It is large enough to be measured without too
much uncertainty and it is small enough to
minimise energy losses to the surroundings.
The metal block heats the surrounding air;
this energy is then removed by convection
currents.
continued
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Physics TBA3
3
By covering the metal block with insulating
material.
The measured value is higher than the actual
value since more energy is needed to heat the
block and replace the energy lost.
1 kg of different metals contains different
numbers of atoms.
4
5
Sample results
These results were obtained using 1 kg metal
blocks and a 24 W heater.
Material
initial temp.
in °C
final temp.
in °C
current
in A
voltage
in V
time
in s
brass
18
29
2.0
12.0
175
382
iron
21
30
2.0
12.0
180
480
copper
19
31
2.0
12.0
200
400
aluminium
22
33
2.0
12.0
405
884
64
= (current voltage × time)
÷ (1 kg × temperature rise)
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Physics TBA3
Aim
Materials required
per
group
Wooden board approximately 1 m long
1
1 kg mass
1
This experiment teaches students that the work
done in moving an object is calculated using
work = force × distance moved.
Metre rule
1
0–10 N forcemeter
1
Students calculate the gravitational potential
energy gained when an object is raised vertically
using weight × vertical height.
Wooden blocks for raising one end of the
board
Students find that the efficiency of a machine is
the fraction of the energy input that becomes
useful energy output, efficiency = useful energy
output ÷ total energy input.
■
make it useful for Sc1 Obtaining Evidence.
■
High achievers should use the results to plot a
graph of efficiency against height of slope.
■
For low achievers, the activity can be simplified
by completing the first two blank columns of
the table (using the sample results).
Activity procedure
1
Students measure the energy input needed to
raise a load by lifting it vertically and by
dragging it up a slope.
2
Students calculate the efficiency of a ramp and
investigate how the efficiency changes with
increasing steepness of the slope.
Other resources
per ( )
groups
Each group requires a large amount of space.
Depending on the space available, this may dictate
the number of students in each group.
Material preparation
The materials used for this activity are very similar
to those for Activity 2.4 on Friction.
Sc1 match
Planning
Not available
Obtaining
available
Analysing
available
Evaluating
available
Answers
2
3
4
5
6
7
Key skills match
✓
Dragging the mass up the slope.
Work has to be done against friction.
The same amount whether it is lifted or
dragged.
Dragging enables a smaller force to be used.
More work has to be done.
The steeper the slope, the greater the
efficiency.
Communication
Sample results
ICT
These results were obtained using a distance,
s = 0.80 m.
Height of ramp,
h in m
Force needed to lift
mass vertically
h in N
Work done in lifting
mass vertically in J
Force to drag mass
through distance s
up slope in N
Work done in
dragging mass up
slope in J
Efficiency = work in
lifting mass ÷ work in
dragging mass
0.10
9.8
0.98
4.4
3.52
0.28
0.20
9.8
1.96
5.3
4.24
0.46
0.30
9.8
2.94
5.9
4.72
0.63
0.40
9.8
3.92
6.6
5.28
0.74
0.50
9.8
4.90
7.3
5.84
0.84
65
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Physics
Topic help Introduction
Using Topic help
The Heinemann/OCR Physics book is written for a wide range of student ability. Topic help is
intended to provide additional help for students with particular learning difficulties.
Students have such a wide range of learning difficulties. Topic help is provided on paper and
CD-ROM so that the teacher can tailor help for the particular difficulties of individual students
or groups of students.
Many students find difficulty understanding and using scientific vocabulary. Throughout the
book, key words have been identified for each double-page spread. Each of these words is defined
in the Glossary. Topic help tries to confirm the correct meaning and use of these words. If this
can be done, it should make the book more accessible.
Each Topic help page supports one double-page spread in the book,
provided that the double page has key words. The learning page is divided
into four parts.
1
A list of Key words for the double-page spread.
2
A brief definition of each of the Key words. Students could match
each of the definitions with the Key words. This could be done by
individual students or could be done with a group using an overhead
projector.
1
2
3
4
3
The Key words are repeated, but sometimes other useful words are
added. These might help in answering the questions in 4.
4
A series of questions that help to use the Key words in the correct context.
The teacher can adapt these questions by removing unwanted questions, adding other questions,
or providing more or less information.
66
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Physics TB1
■
■
■
■
■
■
■
■
current
diode
electron
energy
light dependent
resistor
light emitting
diode
resistance
thermistor
variable resistor
Electric circuits
1
You need this to do work.
2
A flow of electric charge.
3
It reduces the current in a circuit.
4
It changes resistance when light shines on it.
5
It changes resistance when warmed.
6
Use this to change the resistance in a circuit.
7
It only allows current in one direction.
8
A very small negative particle.
9
It shines when a current passes through it.
✂
■
Topic help 1.1A
Topic help 1.1B
Physics TB1
■
■
■
■
■
■
■
■
■
current
diode
electron
energy
light dependent
resistor
light emitting
diode
resistance
thermistor
variable resistor
Electric circuits
1
2
What do these circuit symbols represent?
(a)
_______________________________________
(b)
_______________________________________
(c)
_______________________________________
(d)
_______________________________________
(e)
_______________________________________
(f)
_______________________________________
Draw on the circuit diagram, an arrow to show the direction of the
current.
67
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Physics TB1
■
■
■
■
■
ammeter
ampere
parallel
volt
voltmeter
Topic help 1.2A
Electric circuits
1
A meter used to measure voltage is called a
2
Electric current is measured in units called
3
When current divides to pass through two resistors, the resistors
are in
4
Voltage is measured in units called
5
A meter used to measure current is called an
✂
Topic help 1.2B
Physics TB1
■
■
■
■
■
■
■
■
ammeter
ampere
current
parallel
series
volt
voltage
voltmeter
Electric circuits
1
What do these circuit symbols represent?
(a)
A
_______________________________________
(b)
V
_______________________________________
2
Add the correct letter to the meter symbols. Write in the boxes.
3
Finish the sentences.
(a) A voltmeter is connected in ___________________ with a
resistor.
(b) An ammeter is connected in ___________________ with a
resistor.
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Physics TB1
■
■
milliamp
ohmic
semiconductor
Electric circuits
1
A material which is not a very good conductor but is not an
insulator either.
2
A very small unit of electric current.
3
A material which obeys Ohm’s Law is
✂
■
Topic help 1.3A
Topic help 1.3B
Physics TB1
■
■
■
milliamp
ohmic
semiconductor
Electric circuits
1
What is the symbol for milliamp? ___________________
2
How many milliamps are there in one amp? ___________________
3
Put a ring around the material which is a semiconductor.
copper
iron
plastic
rubber
silicon
4
Put a ring around the graph which shows the behaviour of an
ohmic material.
V
V
I
V
I
V
I
I
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Physics TB2
■
■
■
■
■
■
couple
equilibrium
moment
newton metre
pivot
torque
Topic help 2.1A
Forces and energy
1
The turning effect of a force.
2
Two equal and opposite turning forces are called a
3
The turning effect of two equal and opposite forces.
4
The place where a lever balances is called a
5
Moment is measured in units called
6
A balanced lever is in
Topic help 2.1B
Physics TB2
■
■
■
■
■
■
■
couple
equilibrium
leverage
moment
newton metre
pivot
torque
Forces and energy
1
For each see-saw, write down which side (left or right) goes up or if
it is balanced.
___________________________________
400 N
500 N
1.5 m
2.0 m
___________________________________
400 N
300 N
1.5 m
2.0 m
___________________________________
400 N
500 N
2.5 m
2
70
2.0 m
Finish the sentence.
A screwdriver can help remove the lid of a paint tin easier than a 10p
coin. This is because the screwdriver has more ___________________ .
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Physics TB2
■
■
■
gradient
speed
tangent
Topic help 2.2A
Forces and energy
How fast something is moving.
Steepness of a graph.
A line drawn to touch, but not cross, a curve is called a
Topic help 2.2B
Physics TB2
■
■
gradient
speed
tangent
Forces and energy
1
Look carefully at these graphs. They
show how five bodies moved.
(a) Which body was moving for
the longest time?
___________________
A
B
C
Distance
■
D
E
(b) Which body was moving the
fastest? ___________________
Time
(c) Which two bodies moved the
same distance ___________________ and ___________________
(d) Which body started at a different place to all of the others?
___________________
(e) Which body was moving the slowest? ___________________
2
A car travels 90 km in 1½ hours. What is its average speed in km/h?
___________________ km/h
3
The diagrams show some lengths of
tickertape. A dot is put on the tape
every 1/50 second.
(a) Which tape was changing speed
as the dots were put on the tape?
___________________
A
B
C
(b) Which tape was moving the slowest but at a constant speed?
___________________
71
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Physics TB2
■
■
■
■
displacement
scalar
vector
velocity
Topic help 2.3A
Forces and energy
How fast something is moving in a straight line.
Something which has a size and a direction.
Something which has a size but no direction.
Distance moved in a straight line.
Topic help 2.3B
Physics TB2
■
■
■
displacement
scalar
vector
velocity
Forces and energy
1
A car travels in a straight line between two points 1000 m apart. It
takes 40 s to travel the distance. What is the average velocity of the
car? ___________________ m/s
2
Speed is a scalar. Put rings around two other scalars in this list.
displacement
mass
temperature
velocity
3
Look at this displacement–time for a car journey.
Displacement
■
Put rings around the statements which correctly describe the car
journey.
The car finished its journey at the same place as it started.
The car was never travelling at a constant velocity.
The car was stationary at position C.
The car was not stationary at position D.
72
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■
■
■
■
acceleration
deceleration
gravity
retardation
Topic help 2.4A
Forces and energy
1
These two words mean the same.
___________________ and ___________________
2
Getting faster.
3
Attraction between the Earth and all objects on the Earth.
Topic help 2.4B
Physics TB2
■
■
■
acceleration
deceleration
gravity
retardation
Forces and energy
1
Look carefully at these graphs. They show how five bodies moved
during a certain length of time.
A
B
Velocity
■
C
D
E
Time
(a) Which body was travelling at a constant velocity?
___________________
(b) Which body was slowing down? ___________________
(c) Which two bodies started at rest? ___________________ and
___________________
(d) Which body had the largest acceleration? ___________________
(e) Which body was moving the slowest at the end of the period of
time? ___________________
2
A stone falls from the top of a cliff onto the the beach below. It
2
accelerates at 10 m/s .
(a) What is its velocity one second after it starts to fall?
___________________ m/s
(b) What force caused it to fall? ___________________
3
A car is travelling at 100 km/h. A dog runs into the road in front of
the car. The car slows down.
When the car slows down its v___________________ gets smaller.
This is known as d___________________.
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Physics TB2
■
■
■
■
■
■
■
■
air resistance
drag
force
friction
lift
tension
thrust
weight
Topic help 2.5A
Forces and energy
1
A pull or push of one object on another.
2
The force in a stretched spring.
3
A slowing down force as something moves through the air.
4
A contact force between two sliding objects.
5
Upward force on an aircraft wing, for example.
6
Force on an object acting vertically downwards.
7
A force from a rocket engine, for example.
8
A force which opposes motion through a liquid or gas.
Topic help 2.5B
Physics TB2
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air resistance
drag
force
friction
gravity
lift
tension
thrust
weight
Forces and energy
1
What type of force causes each of the following?
(a) A hot air balloon to rise. ___________________
(b) A ball rolling across grass to stop. ___________________
(c) A tile to fall from a roof. ___________________
(d) A diver to slow down on entering water. ___________________
(e) A catapult elastic to spring back. ___________________
2
The helicopter has four forces acting on it. Name them.
F1 ___________________
F2 ___________________
F3 ___________________
F4 ___________________
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balanced
resultant
streamlined
unbalanced
Topic help 2.6A
Forces and energy
1
The total force acting on a body.
2
Two or more forces which cancel out.
3
Forces which do not cancel out.
4
A shape which cuts down drag forces.
Topic help 2.6B
Physics TB2
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balanced
resultant
streamlined
unbalanced
Forces and energy
1
2
The pictures show helicopters with forces acting on them.
The length of the arrows indicates the size of the force. Answer
true or false to each statement about how each helicopter moves.
(a) Up and forwards
___________________________
(b) Up only
___________________________
(c) Down and back
___________________________
(d) Hovering still
___________________________
Put a ring around the shape which will fall fastest through water.
sphere
cube
cone
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gravitational
potential
joule
kinetic
newton
power
watt
work
Topic help 2.8A
Forces and energy
1
Energy is measured in units called
2
Weight is measured in units called
3
Power is measured in units called
4
What is done when a force is moved through a distance.
5
The rate at which a force is moved through a distance.
6
Energy of a body because of its position above the ground.
7
Energy of a body because of its velocity.
Topic help 2.8B
Physics TB2
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gravitational
energy
potential energy
joule
kinetic
newton
power
watt
work
Forces and energy
1
Units are often named after famous scientists.
These have names which are the same as the units for work, force
and power.
Who were the scientists?
___________________
2
___________________
___________________
A golf ball on a crazy golf hole goes up and down mounds on its
way to the hole. It takes this path.
(a) Where does the ball have most kinetic energy?
___________________
(b) Where does the ball have most gravitational potential energy?
___________________
(c) Where does the ball have least gravitational potential energy?
___________________
(d) Where does the ball not change gravitational potential energy?
___________________
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braking distance
reaction time
stopping distance
thinking distance
Topic help 2.9A
Forces and energy
1
How long does it take for the brain to respond to a signal?
2
How far does a car travel while the brain is responding to a signal?
3
How far does a car travel from when the driver puts his foot on the
brake to when the car stops?
4
The total distance travelled by a car before it stops.
Topic help 2.9B
Physics TB2
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braking distance
reaction time
stopping distance
thinking distance
Forces and energy
1
The Highway Code states thinking, braking and stopping distances
at different speeds.
(a) At 20 miles per hour, John’s thinking distance is 7 m and his
braking distance 8 m. What is his stopping distance?
___________________
(b) At 30 miles per hour, is his thinking distance less than 7 m,
7 m or more than 7 m? ___________________
(c) At 60 miles per hour, the stopping distance stated in the
Highway Code is 74 m. How would this distance change if the
road was wet? ___________________
2
Put rings around the things which might affect a person’s thinking
distance.
age of driver
amount of alcohol drunk by driver
make of car
state of brakes
outside temperature
3
Put rings around the things which might affect a person’s braking
distance.
age of driver
amount of alcohol drunk by driver
road surface
state of brakes
time of day
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air resistance
gravity
terminal velocity
Topic help 2.10A
Forces and energy
1
The force which acts on falling objects.
2
The fastest a falling object can go.
3
A slowing down force as something moves through the air.
Topic help 2.10B
Physics TB2
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air resistance
gravity
terminal velocity
78
Forces and energy
1
A sky-diver jumps out of a plane and falls to Earth. She reaches her
maximum velocity. She then opens her parachute. Does her
velocity increase, decrease or stay the same?
2
The diagram shows a ball falling through syrup. Its position is
shown at half-second intervals. Where did it reach its terminal
velocity?
3
In which direction does air resistance act on a
falling body?
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conduction
convection
insulator
machine
pay back period
radiation
Topic help 2.11, 2.12A
Forces and energy
1
Thermal energy is transferred through liquids by
2
Thermal energy is transferred through solids by
3
Thermal energy is transferred through space by
4
A poor conductor
5
It allows work to be done more easily.
6
The time it takes to recover money spent on insulating a home.
Topic help 2.11, 2.12B
Physics TB2
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conduction
convection
insulator
pay back period
radiation
Forces and energy
1
(a) Which thermal energy transfer
cork
process is taking place in the
water? ___________________
(b) In which direction does the cork
move? ___________________
2
(a) Which thermal energy transfer
process is taking place from the
flame to the hand through the rod?
___________________
(b) What type of material could be used for
a handle to stop the person being
burned? ___________________
3
Which thermal energy transfer process is taking
place from the potato? ___________________
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compression
electromagnetic
wave
longitudinal wave
rarefaction
transverse wave
vibration
Topic help 3.1A
Wave properties
1
A wave family which includes light.
2
A wave whose displacement is in the same direction as its motion.
3
A wave whose displacement is at right angles to its direction of
motion.
4
The to and fro motion of a particle.
5
Area of a wave where particles are closer together than normal.
6
Area of a wave where particles are further apart than normal.
Topic help 3.1B
Physics TB3
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compression
electromagnetic
wave
longitudinal wave
rarefaction
transverse wave
vibration
80
Wave properties
1
Put rings around the waves which are not electromagnetic waves.
infrared
sound
radio
ultraviolet
water
X-rays
2
Write the letter R at the centre of a rarefaction and the letter C at
the centre of a compression.
3
Use a double headed arrow (←→) to show the direction of
displacement of particles in the transverse wave.
4
Use a double headed arrow (←→) to show the direction of
displacement of particles in the longitudinal wave.
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amplitude
frequency
hertz
speed
velocity
wavelength
Topic help 3.2A
Wave properties
1
Frequency is measured in units called
2
The distance between two points of similar displacement.
3
The maximum displacement of a wave from its rest position.
4
The number of complete waves passing a point each second.
5
The rate of change of distance with time.
6
The rate of change of distance with time in a straight line.
Topic help 3.2B
Physics TB3
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amplitude
frequency
hertz
speed
velocity
wavelength
Wave properties
1
This is a transverse wave.
x
y
(a) What does the distance x represent? ___________________
(b) What does the distance y represent? ___________________
2
This is a longitudinal wave.
What does the distance z represent? ___________________
3
A duck on a lake bobs up and down on the waves 10 times in
20 seconds. What is the frequency of the waves?
___________________
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concave
converge
convex
diverge
focus
plane
pulse
ripple tank
stroboscope
wavefront
Topic help 3.3A
Wave properties
1
The point at which waves converge.
2
A surface which curves inwards.
3
A surface which curves outwards.
4
Wave paths getting closer together.
5
Wave paths getting further apart.
6
The position of a wave at a given point in time.
7
A flat or straight surface.
8
A single wave.
9
Scientific apparatus used to study water waves.
10
Instrument which makes waves appear to be still.
Topic help 3.3B
Physics TB3
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concave
converge
convex
diverge
focus
plane
pulse
ripple tank
stroboscope
wavefront
Wave properties
1
The arrows show the directions of water waves.
(a) What is the shape of the surface
s
which caused the wave pattern?
u
r
f
a
___________________
(b) Mark the focus with an X.
(c) Finish the missing word. The waves
d_ _ _ _ _ _ from the focus.
2
A wave pulse is made in a ripple tank
by dropping a small piece of rubber into the water. Draw the shape
of the wavefront.
Small piece
of rubber
82
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Ripple
tank
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diffuse
echo
glancing angle
incident ray
normal
reflected ray
refraction
reverberation
Wave properties
1
A line drawn at 90° to a surface. ___________________
2
A ray travelling towards a mirror. ___________________
3
A ray travelling away from a mirror.
4
The angle between a ray and a mirror.
5
Scattered reflection. ___________________
6
Reflection of sound. ___________________________________________
7
Repeated reflection of sound.
8
The change in direction of a wave at a boundary.
Physics TB3
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diffuse
echo
glancing angle
incident ray
normal
reflected ray
refraction
reverberation
Wave properties
1
Light is reflected from a mirror.
(a) Write the letter N on the normal.
(b) Write the letter I on the incident ray.
(c) Write the letter R on the reflected ray.
(d) Write the letter G in the glancing angle.
2
A ray of light is travelling towards a glass block.
glass
block
(a) Write the letter N on the normal.
(b) Continue the path of the ray into the glass block.
(c) What is happening to the light as it passes into the glass?
Use a word from the list. ___________________
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apparent depth
diffraction
image
no-parallax
real depth
real image
virtual image
Wave properties
1
A reproduction of an object formed by a lens or mirror.
2
It can be projected onto a screen.
3
It only appears to be there.
4
The spreading out of a wave after it passes through a gap.
5
The distance of an object below the surface.
6
Where the object appears to be below the surface.
7
When an object and image are lined up together.
Physics TB3
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apparent depth
diffraction
image
no-parallax
real depth
real image
virtual image
Wave properties
1
Put rings around the images which are real.
image formed by a plane mirror
image formed by a pinhole camera
image formed by a convex mirror
image formed by an overhead projector
2
A fisherman is watching a fish.
(a) Mark and label on the
diagram the real depth of
the fish.
(b) Mark and label on the
diagram the apparent depth
of the fish.
3
Joe uses a voltmeter. There is a
mirror under the scale. His teacher tells him that this will help Joe
to read the pointer accurately. He moves his head until he finds
no-parallax. Where is the image of the pointer?
Put a ring around the correct answer.
to the left of the pointer
behind the pointer
to the right of the pointer
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fluorescent
infrared
radio
spectrum
ultraviolet
visible light
X-rays
Topic help 4.1A
Using waves
1
The cause of a suntan.
2
Radiation from a warm body.
3
Used for examining broken bones.
4
Energy sources arranged in order of wavelength.
5
A light-emitting substance.
6
Waves used for communication.
7
Type of wave to which our eyes are sensitive.
Topic help 4.1B
Physics TB4
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fluorescent
infrared
radio
spectrum
ultraviolet
visible light
X-rays
Using waves
1
Which colour in the visible spectrum is next to infrared?
2
Put rings around the colours which are not colours in the visible
spectrum.
red
yellow
pink
green
orange
purple
blue
3
Radio waves are used to send messages long distances. What other
type of wave is used for sending messages long distances?
4
What is the speed of all electromagnetic waves in air?
5
Police officers often wear special jackets to make them more
visible. This is particularly true at night. What type of material is
the jacket made from? F______________________________________
6
Which part of the television set in your home fluoresces?
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thermistor
thermograph
Topic help 4.2A
Using waves
1
An electronic device whose resistance changes with temperature.
2
A picture formed by recording different temperatures.
Topic help 4.2B
Physics TB4
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thermistor
thermograph
Using waves
1
How can you tell, just by looking, that a coal fire is hotter than an
electric iron?
2
Which part of the electromagnetic spectrum makes us feel hot
when the sun shines?
3
Which part of the electromagnetic spectrum gives us a tan when
the sun shines?
4
Put a ring around the things which work because of infrared
radiation.
electric bar fire
fluorescent lighting
night sights
remote control for hi-fi unit
security marking of personal property
5
One day in June, the normal burn time in the sun is 15 minutes.
Draw a line from each time that a person wants to spend in the
Sun, to the correct minimum sun screen factor.
factor 2
four hours
factor 5
one hour
factor 10
three hours
factor 15
two hours
factor 20
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aerial
gamma ray
ionosphere
microwave
radar
radio
satellite
X-rays
Topic help 4.3A
Using waves
1
Device used to receive or transmit radio signals.
2
A body orbiting Earth.
3
Electromagnetic radiation given out in radioactive decay.
4
High-energy electromagnetic radiation capable of penetrating skin
but not bone.
5
Communication waveband in the electromagnetic spectrum.
6
Electromagnetic waves used for cooking.
7
The use of reflected radio waves to measure distance.
8
Part of the upper atmosphere, capable of reflecting some radio waves.
Topic help 4.3B
Physics TB4
Using waves
1
Draw a line from each wave box to the correct wavelength box.
2 mm
long wave radio
2m
medium wave radio
200 m
microwave
2 km
short wave radio
200 km
2
All luggage is scanned at airport baggage handling centres.
What type of electromagnetic wave is used to scan the luggage?
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critical angle
digital signal
endoscope
optical fibre
prism
total internal
reflection
Topic help 4.4A
Using waves
1
Device used to look inside the body.
2
Very small diameter length of glass along which light passes.
3
Regular shaped block of glass.
4
The behaviour of light in a dense material if the angle of incidence
is too large.
5
A series of pulses which may be either on or off.
6
An angle of incidence which produces an angle of refraction of 90°.
Topic help 4.4B
Physics TB4
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critical angle
digital signal
endoscope
normal
optical fibre
prism
total internal
reflection
Using waves
1
Put rings around the digital signals.
2
A ray of light is travelling towards a glass block.
(a) Angle A is 45°. What happens at I?
(b) Finished the diagram to show the path of the ray.
(c) Finish labelling the diagram.
a
A
of
i
I
n
p
3
What is used in an endoscope to transmit the light into the patient
and the reflected light back to the eyepiece?
O___________________ f___________________
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sonar
ultrasound
Topic help 4.5A
Using waves
1
High-frequency sound, beyond the range of human hearing.
2
The use of sound waves to measure distance or aid navigation.
Topic help 4.5B
Physics TB4
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echolocation
sonar
ultrasound
Using waves
1
Which three animals
navigate by
echolocation?
Put rings around the
right answers.
2
A boat searches
whilst it is at sea.
What could it locate
using sonar?
Underline the right
answers.
aircraft
overhead
Bat
Cat
Dog
Dolphin
Elephant
Rat
other boats
sea bed
shoal of fish
submarine
sunken
wreck
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continental drift
core
crust
lava
lithosphere
magma
mantle
volcanic ash
Topic help 4.7A
Using waves
1
Molten rock below the surface.
2
Molten material from a volcano extruded onto the Earth’s surface.
3
Rock blasted out from a volcano.
4
The centre of the Earth.
5
The outer layer of the Earth.
6
The major part of the Earth, between the centre and outer layer.
7
The outer part of the mantle and lower part of the crust.
8
Theory which explains the movement of continents over long
periods of time.
Topic help 4.7B
Physics TB4
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continental drift
core
crust
lava
lithosphere
magma
mantle
volcanic ash
Using waves
1
c
m
c
2
90
Finish labelling the diagram of the structure of the Earth.
The figure shows a volcano erupting. Label the lava and the
volcanic ash.
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asthenosphere
constructive
boundary
destructive
boundary
metamorphism
plate
sea-floor spreading
subduction zone
trench
Topic help 4.8A
Using waves
1
A layer of floating mantle.
2
Change of state of rock due to pressure and heat.
3
A section of the Earth’s crust.
4
The moving apart of plates and the formation of new crust by
magma from the mantle.
5
The border between plates where new lithosphere is formed as the
plates separate.
6
The border between plates where lithosphere is destroyed as the
plates collide.
7
Area where an oceanic plate goes below a continental plate.
8
Formed when one plate moves up and over another.
Topic help 4.8B
Physics TB4
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asthenosphere
constructive
boundary
destructive
boundary
metamorphism
plate
sea-floor spreading
subduction zone
trench
Using waves
1
What does this diagram show? Choose your answer from the list on
the left.
Oceanic
crust
Lithosphere
Asthenosphere
Rising magma
2
Many volcanoes are found at plate boundaries. What other events
often happen at plate boundaries?
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alpha particle
antineutrino
atomic number
background
radiation
beta particle
gamma ray
isotope
mass number
radioisotope
Topic help 5.1A
Radioactivity
1
The nucleus of a helium atom.
2
A high speed electron.
3
Penetrating electromagnetic radiation.
4
Atom of an element with a different mass number.
5
A radioactive atom.
6
A particle formed when a neutron changes to a proton and a beta particle.
7
The number of protons in an atom.
8
The number of protons plus neutrons in an atom.
9
Everyday radiation which is always around us.
Topic help 5.1B
Physics TB5
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alpha particle
antineutrino
atomic number
background
radiation
beta particle
gamma ray
isotope
mass number
radioisotope
Radioactivity
1
The diagrams show the nuclei of some atoms. For each atom, write
down the atomic number and the mass number.
(b)
(a)
Key:
2
neutron
proton
A radioactive isotope decays and forms an isotope of an element
one place higher in the periodic table.
(a) What type of radiation is emitted? ___________________
(b) How does the mass compare? ___________________
3
A radioactive isotope decays and forms an isotope of an element
two places lower in the periodic table.
(a) What type of radiation is emitted? ___________________
(b) How does the mass compare? ___________________
4
92
A radiation detector shows a reading even when there are no
radioactive sources in the room. Why?
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film badge
Geiger-Müller
tube
ionisation
radiation
spark counter
Topic help 5.2A
Radioactivity
1
Detector of alpha radiation which relies on air being ionised.
2
Worn by people who use radiation to measure their exposure to the
radiation.
3
Detector of beta and gamma radiation which relies on argon being
ionised.
4
The addition or removal of electrons from an atom.
5
Energy which travels as rays, waves or particles.
Topic help 5.2B
Physics TB5
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film badge
Geiger-Müller
tube
ionisation
radiation
spark counter
Radioactivity
1
Which type of radiation, alpha, beta or gamma, is the most
ionising?
2
Which type of radiation, alpha, beta or gamma, will pass through
thick lead sheets?
3
Which type of radiation, alpha, beta or gamma, has a range of about
1 m in air?
4
Which type of radiation, alpha, beta or gamma, travels at the same
speed as light?
5
Why is it not possible to detect beta and gamma radiation with a
spark counter? Put a ring around the correct answer.
They travel too large a distance.
They are too penetrating.
They do not ionise air enough.
They have the wrong charge.
6
The diagram shows the film from Peter’s
film badge after it has been developed.
The film goes black if it has been exposed
to radiation.
The black area is where the film is not
covered by any plastic or metal. What type
of radiation alpha, beta or gamma has Peter
been mainly exposed to? ___________________
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activity
becquerel
daughter nuclide
decay
half-life
parent nuclide
Topic help 5.3A
Radioactivity
The splitting of an isotope with the emission of radioactivity.
An isotope which emits radiation and changes to an isotope of a
different element.
An isotope which is formed as a result of the splitting of another
isotope.
The time it takes for half the nuclei in a radioactive material to decay.
The rate at which a radioactive source is decaying.
A unit of radioactivity equal to one decay each second.
Topic help 5.3B
Physics TB5
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activity
becquerel
daughter nuclide
decay
half-life
parent nuclide
Radioactivity
1
The graph shows how a radioactive sample decays during a 12 hour
period.
1000
750
Activity
in counts 500
per minute
250
0
0
2
4
6
8
10
12
Time in hours
What is the half-life of the radioactive sample? ___________________
2
Radium-226 decays and emits an alpha particle to form radon-222.
(a) Which is the parent nuclide? ___________________
(b) Which is the daughter nuclide? ___________________
3
A radioactive sample is decaying. It emits 6000 alpha particles each
minute. Write down its activity in becquerels. ___________________
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bacteria
cancer
radiocarbon dating
sterilisation
tracer
Radioactivity
1
Simple organisms which may cause disease. _____________________
2
Tumours which grow out of control. ____________________________
A process for destroying organisms. _____________________________
The technique used for estimating the age of the Turin Shroud.
A radioisotope introduced into a system which allows its
movement through the system to be monitored.
Physics TB5
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alpha radiation
beta radiation
bacteria
cancer
gamma radiation
radiocarbon dating
sterilisation
tracer
Radioactivity
1
Which type of radiation is used to sterilise the scissors used by
surgeons in hospital? ___________________________________________
2
Which type of radiation is used to treat skin cancer? ______________
3
Which type of radiation is used to treat a brain tumour? ___________
4
Which type of radiation is used in a smoke alarm? ________________
5
Which type of radiation is used in a smoke alarm? ________________
6
The half-lives of some carbon isotopes are listed.
carbon-10
carbon-11
carbon-14
carbon-15
carbon-16
19.255 seconds
20.39 minutes
5730 years
2.449 seconds
0.747 seconds
Which isotope is used for radiocarbon dating? _____________
7
Americium-241 is used in smoke alarms. Which properties make it
a good radioisotope to use? Put a ring around the correct answer.
emits alpha radiation and has a short half-life
emits alpha radiation and has a long half-life
emits gamma radiation and has a short half-life
emits gamma radiation and has a long half-life
95
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Physics TB5
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cumulative
DNA
lymphocyte
mutation
radiation burns
radiation sickness
Topic help 5.6A
Radioactivity
1
Illness caused by exposure to radioactivity.
2
Damage to the skin caused by exposure to radioactivity.
3
A molecule which contains coded genetic information.
4
A type of white blood cell.
5
Alterations in genetic material which change the cell.
6
Increasing by repeated addition.
Topic help 5.6B
Physics TB5
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cumulative
DNA
lymphocyte
mutation
radiation burns
radiation sickness
Radioactivity
1
What do the initials DNA stand for? Put a ring around the correct
answer.
deoxyribonucleic acid
di-nitrogen acid
dual nuclear additive
2
Young people have to be a certain age before they are allowed to
handle radioactive material. At what age
can they handle radioactive material?
_____________
3
Three ways in which we protect ourselves
from radioactivity are by using shielding,
distance and time of exposure.
Which way is being used when radioactive
material is taken by lorry in large flasks?
_______________________________________________________________
4
What does this symbol mean?
__________________________________________
96
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Physics TB6
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asteroid
centripetal
comet
geo-stationary
orbit
gravity
planet
polar orbit
satellite
Solar System
Topic help 6.1A
1
Force acting towards the centre of a circle which keeps a body
moving in a circle.
2
Force of attraction between two bodies.
3
Any small body in orbit around a larger body.
4
A large body in orbit about a star.
5
A small rock in orbit around the Sun, between Mars and Jupiter.
6
A small lump of ice and dust orbiting the Sun in a very elongated
elliptical orbit.
7
The part of the Universe which contains the Sun and everything
which is circling around it.
8
A satellite orbit which passes over the North and South Poles.
A satellite orbit above the equator which takes 24 hours to circle
the Earth.
Topic help 6.1B
Physics TB6
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■
■
■
asteroid
centripetal
comet
geo-stationary
orbit
gravity
planet
polar orbit
satellite
Solar System
1
The diagram shows a satellite, S, orbiting Earth, E. Draw an arrow
on the diagram to show the direction of the force acting on the
satellite.
S
E
2
A communications satellite takes 24 hours to orbit the Earth.
A weather satellite takes only 2 hours. Put a ring around the
reason why.
The weather satellite is in polar orbit.
The weather satellite is closer to the Earth.
The weather satellite orbits in the opposite direction.
97
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Physics TB6
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black dwarf
black hole
blue supergiant
nebulae
neutron star
nuclear fusion
protostar
red giant
supernova
white dwarf
Topic help 6.2A
1
An area of space, so dense that not even light can escape.
2
The joining together of light nuclei with the release of energy.
3
A newly formed star.
4
A small star whose fuel has run out.
5
A small, dense collapsed star.
6
An average sized star which expands at the end of its life.
7
A large star with a short life.
8
A faded white dwarf.
9
Clouds of dust and gas.
10
The explosion of a star at the end of its life.
Topic help 6.2B
Physics TB6
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black dwarf
black hole
blue supergiant
nebulae
neutron star
nuclear fusion
protostar
red giant
supernova
white dwarf
1
The Sun contains isotopes of an element which fuse together and
release energy.
(a) The isotopes from which element fuse together? _____________
(b) Which element is formed by the fusion process? _____________
2
A protostar is formed when clouds of gas and dust are drawn
together. What type of force draws the gas and dust together?
electrostatic
3
4
98
gravity
magnetic
Arrange the following in order of size starting with the smallest.
red giant
red supergiant
white dwarf
___________________
___________________
___________________
Which star has the longest life – a small star or a large star?
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Physics TB6
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Big Bang
Big Crunch
Doppler effect
quasar
red shift
Topic help 6.3A
1
Probably the brightest object in the Universe.
2
The explosion which scientists believe started the expansion of the
Universe.
3
The possible collapse of the Universe.
4
A visible effect when a galaxy is moving away.
5
The difference in frequency caused by a moving body.
Topic help 6.3B
Physics TB6
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■
■
Big Bang
Big Crunch
Doppler effect
quasar
red shift
1
Put a ring around what was present at the time of the Big Bang.
galaxies
planets
2
nothing
stars
The diagram shows the positions of four galaxies relative to Earth.
E
Earth
G1
G2
G3
G4
(not to scale)
Which galaxy shows the greatest amount of red shift?_____________
3
Light from quasars takes about 12 billion years to reach Earth. Put a
tick next to the statement which is most likely to be true.
The age of the Universe is less than 12 billion years.
The age of the Universe is about 12 billion years.
The age of the Universe is more than 12 billion years.
4
Light from a nearby galaxy appears bluer than expected. Finish the
sentences.
The name of this effect is b_____________ shift. It means that the
galaxy is moving t_____________ us.
5
Bobbie is listening to the siren on an ambulance. The pitch is
increasing. Is the ambulance moving towards or away from Bobbie?
_____________
99
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Physics TB7
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■
charge
conductor
electron
friction
insulator
neutron
nucleus
proton
repel
van de Graaff
generator
Topic help 7.1A
Using electricity
1
A positively charged particle.
2
A neutral particle.
3
A negatively charged particle.
4
The central region of an atom.
5
The flow in an electric circuit.
6
A material which has low resistance.
7
A material which does not allow an electric current to pass through it.
8
A device which uses electrostatics to produce high voltages.
9
The result of two similar charges close together.
10
The force between two surfaces rubbing together.
Topic help 7.1B
Physics TB7
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■
■
■
charge
conductor
electron
friction
induction
insulator
neutron
nucleus
proton
repel
van de Graaff
generator
Using electricity
1
When two surfaces rub together they may become charged.
One surface gains electrons and the other loses electrons.
(a) What is the charge on the surface which gains electrons?
(b) What is the charge on the surface which loses electrons?
2
Why is an atom neutral (uncharged)? Put a ring around the correct
answer.
Atoms contain only neutrons.
Atoms have the same number of protons as electrons.
Atoms are conductors and lose charge.
3
Two charged spheres attract. The charge on one of the spheres is
positive. What is the charge on the other? _____________
4
A negatively charged balloon sticks to a wall. The wall has become
positively charged by i_____________
100
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Physics TB7
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fuel
inert
lightning
photocopier
precipitator
toner
Topic help 7.2A
Using electricity
1
Powdered ink. _________________________________________________
2
Electrostatic device which is used to duplicate a document.
3
Electrostatic device which is used to reduce pollution from factory
chimneys. ____________________________________________________
4
A chemical which is non reactive. ______________________________
5
A chemical which is burned to release energy. ___________________
6
A high-voltage spark from a cloud. ______________________________
✂
Topic help 7.2B
Physics TB7
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■
fuel
inert
lightning
photocopier
precipitator
toner
Using electricity
1
A precipitator in a factory chimney has negatively charged wires.
As the smoke goes up the chimney the same charge is put on the
dust particles. The dust particles are attracted to large metal plates
and stay on them.
(a) What is the charge on the dust particles after they have passed
the wires? _____________
(b) What is the charge on the large metal plates? _____________
2
When aircraft are refuelled, friction can cause the fuel to become
charged. The aircraft and the tanker are joined by a cable. Put a ring
around the correct statement.
The cable is a good conductor to prevent a build-up of charge.
The cable is a poor conductor to allow the charge to leak slowly.
The cable is an insulator to make sure the charge cannot pass.
3
Air is normally an i_____________. If there is a large voltage
difference air can become a c_____________. The voltage difference
between a thundercloud and the Earth may be many thousands of
volts. A spark from a cloud to Earth is called _____________.
4
Liquid fertiliser in a crop sprayer becomes charged as it flows
through the pipes. Which diagram, A, B or C shows how the spray
comes out of the nozzle? ____
A
101
B
C
101
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Physics TB7
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charge
conventional
current
coulomb
electron
ion
Topic help 7.3A
Using electricity
1
Charge is measured in units called
2
A small negatively charged particle.
3
An atom which has gained or lost negative charge.
4
The flow in an electric circuit.
5
The opposite direction to the flow of electrons in an electric circuit.
✂
Topic help 7.3B
Physics TB7
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■
charge
conventional
current
coulomb
electron
ion
Using electricity
1
The diagram shows a simple circuit.
(a) Draw on the diagram an arrow to show the direction of
conventional current. Label this arrow X.
(b) Draw on the diagram an arrow to show the direction of flow of
charge. Label this arrow Z.
2
A current from a battery is passed through a
solution of salt water. The salt water contains
positive and negative ions.
Which type of ion moves towards the positive
terminal of the battery?
102
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Physics TB7
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alternating current
direct current
earth
fuse
live
neutral
watt
Using electricity
1
The wire which carries current to domestic appliances.
2
The wire which provides a return path for current from a domestic
appliance.
3
The wire which should carry no current unless a fault occurs.
4
A thin wire which breaks if the current gets too large.
5
Power is measured in units called
6
Current from the mains supply.
7
Current from a battery.
✂
■
Topic help 7.4A
Topic help 7.4B
Physics TB7
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■
■
■
alternating current
direct current
earth
fuse
live
neutral
watt
Using electricity
1
Finish the table by writing in the colours of each wire when
connected to a normal 13A plug.
wire
colour
live
neutral
earth
2
The current in an electric kettle is 8A. What fuse should be put in
the plug. Put a ring around the correct answer.
2A
3
5A
13A
Jane connects a bulb and a d.c. ammeter to a 12V a.c. power pack.
Put a ring around the correct statement.
The bulb lights but the
ammeter vibrates around 0A.
The bulb does not light and the
ammeter reads 0A.
The bulb does not light and the
ammeter vibrates around 0A.
A
103
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Physics TB7
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circuit breaker
double insulation
electric shock
kilowatt-hour
residual current
device
short circuit
Using electricity
1
Wiring of an electrical appliance in a way that no live wire can
possibly touch the casing.
2
Symptoms after an electric current has passed through the body.
3
The electricity supply companies measure electrical energy in units
called
4
The joining together of live and neutral wires without passing
through the appliance.
5
Switch which turns off the current when it reaches a certain value.
6
Switch which turns off the current when a small difference between
the value of current in the live and neutral wires is detected.
✂
Physics TB7
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■
■
■
circuit breaker
double insulation
electric shock
kilowatt-hour
residual current
device
short circuit
Using electricity
1
What does this symbol on an electrical appliance mean?
2
A 2 kW fan heater is used for three hours.
(a) How much electrical energy has been used?____________ units.
(b) Electricity costs 7p per unit. How much does the heater cost to
use for three hours? _____________p
3
Finish these sentences
The live wire in a metal kettle is loose and touches the case. The
metal is connected to e_____________. A large c_____________
passes through the l_____________ wire. This melts the
f_____________.
4
Put a tick next to each correct statement about residual current
devices.
An RCD does not detect a short circuit.
An RCD does not detect a large current in the live wire.
An RCD should be used as well as (not instead of) a fuse.
104
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Physics TB8
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Fleming’s
left-hand rule
iron core
loudspeaker
motor
radial field
split-ring
commutator
Electromagnetism
1
A device which uses an electric current in a magnetic field to
produce motion.
2
Used to predict the direction of motion.
3
The field produced by the concave poles of a horseshoe magnet.
4
Former on which a coil is wound to increase the strength of the
magnetic field.
5
Part of a motor which reverses the current direction in the coil.
6
Device which works on the motor principle which vibrates to
produce sound.
✂
■
Topic help 8.1 and 8.2A
Topic help 8.1 and 8.2B
Physics TB8
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■
■
■
Fleming’s
left-hand rule
iron core
loudspeaker
motor
radial field
split-ring
commutator
Electromagnetism
1
The diagram shows a wire passing between the poles of magnets.
In which direction will the wire move when the switch is closed?
N
S
2
Which arrangement of magnetic poles will produce a radial field?
Choose A, B or C.
N
S
A
3
N
N
N
B
S
C
Put a ring around the change which will decrease the speed of a
motor.
increase number of turns on coil
increase current in wire
increase distance between magnetic poles
105
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Physics TB8
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Faraday’s Law
Fleming’s
right-hand rule
induced current
induced voltage
Topic help 8.3A
Electromagnetism
1
Used to predict the direction of the current.
2
Relates the speed of cutting magnetic field lines to the voltage
produced.
3
Current produced when a wire moves through a magnetic field.
4
Voltage produced when a wire moves through a magnetic field.
✂
Topic help 8.3B
Physics TB8
■
■
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■
Faraday’s Law
Fleming’s
right-hand rule
induced current
induced voltage
Electromagnetism
1
2
The diagram shows a wire
moving downwards between the
poles of magnets. In which
direction A or B will
conventional current be
produced? ___________________
Michael winds a coil of wire around a
magnet. He attaches the ends of the
wire to an ammeter.
A
N
S
B
N
(a) What is the reading on the
ammeter? ___________________
(b) What three things can Michael do
to increase the current?
Put rings around the correct answers.
increase the number of turns on the coil
decrease the number of turns on the coil
increase the strength of the magnet
decrease the strength of the magnet
move the magnet out of the coil
change the ammeter for a more sensitive one
106
S
A
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Physics TB8
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alternator
dynamo
mutual induction
slip rings
Electromagnetism
1
Device which uses mechanical energy to produce an electric
current.
2
An a.c. generator.
3
The production of a voltage in a coil of wire by the changing
magnetic field from an adjacent coil.
4
Device which conducts current via carbon brushes from the coil of
an a.c. generator.
✂
■
Topic help 8.4A
Topic help 8.4B
Physics TB8
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■
■
■
alternator
dynamo
mutual induction
slip rings
Electromagnetism
1
The diagram shows two coils wound onto a
wooden rod. One coil is connected to a
switch and a battery. The other coil is
connected to an ammeter.
(a) What is the reading on the ammeter
when the switch is open?
(b) What happens when the switch is
closed? Put a ring around the correct
answer.
A
The needle of the ammeter stays still.
The needle deflects then returns to
zero.
The needle deflects and stays deflected.
(c) What happens when the switch is opened again? Put a ring
around the correct answer.
The needle of the ammeter stays still.
The needle deflects the opposite way then returns to zero.
The needle deflects the opposite way and stays deflected.
(d) What happens if the wooden rod is replaced with an iron rod?
The current induced in the bottom coil is ___________________ .
107
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Physics TB8
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primary
secondary
step-down
step-up
eddy current
laminated
Topic help 8.5A
Electromagnetism
The input coil of a transformer.
The output coil of a transformer.
A transformer whose output voltage is greater than the input.
A transformer whose output voltage is less than the input.
Arrangement of thin layers of iron in the core of a transformer.
Induced in the core of a transformer.
✂
Topic help 8.5B
Physics TB8
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■
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■
■
■
primary
secondary
step-down
step-up
eddy current
laminated
Electromagnetism
1
The diagram shows a transformer.
Primary
coil
Iron
(a) Finish labelling the diagram.
(b) What type of transformer, step-up or step-down, is shown?
(c) A 12 V d.c. supply is connected to the primary coil. Why is
there no output from the secondary coil? Put a ring around the
correct answer.
The voltage is too low to make the transformer work.
Transformers only work if the voltage is a.c.
Iron is the wrong material on which to wind the coils.
108
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Physics TB8
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acid rain
exciter
global warming
pollution
renewable energy
superheated steam
power station
Electromagnetism
1
The raising of the average temperature of the Earth.
2
Damage to the environment caused by man.
3
Oxides of sulphur dissolved in water.
4
d.c. generator providing current for electromagnets in a power
station.
5
Water boiled at high pressure.
6
Source of energy which is not used up or which is replaced quickly.
7
Complex which produces electricity from another energy source.
✂
■
Topic help 8.6A
Topic help 8.6B
Physics TB8
■
■
■
■
■
■
acid rain
exciter
global warming
pollution
renewable energy
superheated steam
power stations
■ coal-burning
■ gas-fired
■ hydroelectric
■ nuclear
■ oil-fired
Electromagnetism
1
Which three types of power station burn fossil fuels to produce
electricity? Choose your answers from the list.
_________________________
_________________________
_________________________
2
Which type of power station uses a renewable energy source?
Choose your answer from the list. ___________________
3
Which type of power station uses radioactive elements as a source?
Choose your answer from the list. ___________________
4
What damage does acid rain do to buildings?
5
What damage does acid rain do to plants and animals?
6
Put rings around other sources of energy which are being
developed.
geothermal
lightning
solar
tide
wind
wave
109
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Physics TB8
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■
National Grid
power loss
substation
transmission
Topic help 8.7A
Electromagnetism
1
The difference between the power generated and the power
available for use.
2
Distribution network carrying electricity from power station to
consumers.
3
The movement of electricity from one place to another.
4
A local transformer.
✂
Topic help 8.7B
Physics TB8
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■
■
■
National Grid
power loss
substation
transmission
Electromagnetism
1
Electricity leaves the power station with a voltage of 25 000 V.
400 000 V
Power
station
25 000 V
Home
230 V
(a) The overhead power lines carry the electricity with a voltage of
400 000 V. What type of transformer is used to change the voltage?
(b) Local substations change the voltage back to 230 V to use at
home. What type of transformer is in the local substation?
2
Electricity is transmitted around the country at high voltages. This
means that the c___________________ is small. Energy is lost from
the wires in the form of h___________________. The amount of
energy lost depends on the c___________________, so it is best if this
is as small as possible.
110
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Physics TB1
Topic help answers
TB1 Electric circuits
A
Spread 1.1
A
B
A
1
(a) resistor, (b) diode,
(c) variable resistor,
(d) thermistor,
(e) light emitting diode,
(f) light dependent resistor
2
arrow in anticlockwise
direction
Spread 1.2
A
B
A
햲 Energy 햳 current 햴 resistance 햵 light dependent
resistor 햶 thermistor 햷 variable resistor 햸 diode 햹 electron 햺 light
emitting diode.
햲 Voltmeter 햳 ampere 햴 parallel 햵 volt 햶 ammeter.
1
(a) ammeter, (b) voltmeter
2
A in series V in parallel
3
(a) parallel, (b) series
Spread 1.3
A
B
햲 Semiconductor 햳 ohmic 햴 milliamp
1
mA
3
silicon
2
1000
4
straight line passing through
origin
TB2 Forces and energy
A
Spread 2.1
A
B
A
1
(a) left, (b) balanced,
(c) balanced
2
leverage
2
60
3
(a) C, (b) A
Spread 2.2
A
B
A
햲 Moment 햳 couple 햴 torque 햵 pivot 햶 newton metre
햷 equilibrium.
햲 Speed 햳 gradient 햴 tangent.
1
(a) D, (b) A, (c) A and B, (d) E,
(e) E
Spread 2.3
A
B
햲 Velocity 햳 vector 햴 scalar 햵 displacement.
1
25 m/s
2
mass, temperature
3
The car finished its journey
at the same place as it
started. The car was not
stationary at position D.
111
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Physics TB2
Topic help answers
A
Spread 2.4
A
B
A
1
(a) D, (b) E, (c) A and B, (d) A,
(e) E
2
(a) 10, (b) gravity
3
velocity, decelaration
Spread 2.5
A
B
A
햲 Force 햳 tension 햴 air resistance 햵 friction 햶 lift 햷 weight
햸 thrust 햹 drag
1
(a) lift, (b) friction, (c) gravity,
(d) drag, (e) tension
2
F1 lift, F2 drag/air resistance,
F3 weight, F4 thrust
Spread 2.6
A
B
A
햲 Resultant 햳 balanced 햴 unbalanced 햵 streamlined.
1
(a) true, (b) true, (c) false,
(d) true
2
cone
Spread 2.8
A
B
A
햲 Joule 햳 Newton 햴 Watt 햵 work 햶 power 햷 gravitational
potential 햸 kinetic.
1
Joule, Newton, Watt
2
(a) A, (b) D, (c) F, (d) E
Spread 2.9
A
B
A
햲 Reaction time 햳 thinking distance 햴 braking distance 햵 stopping
distance.
1
(a) 15 m, (b) more than 7 m,
(c) increase
2
age of driver, amount of
alcohol
3
road surface, state of brakes
Spread 2.10
A
B
A
햲 Gravity 햳 terminal velocity 햴 air resistance.
1
decrease
2
E
3
upwards
Spread 2.11+2.12
A
B
112
햲 Decelaration and retardation 햳 acceleration 햴 gravity.
햲 Convection 햳 conduction 햴 radiation 햵 insulator 햶 machine
햷 pay back period.
1
(a) convection, (b) right
2
(a) conduction, (b) insulator
3
radiation
M
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Physics TB3
Topic help answers
TB3 Wave properties
A
Spread 3.1
A
B
A
햲 Electromagnetic wave 햳 longitudinal wave 햴 transverse
wave 햵 vibration 햶 compression 햷 rarefaction.
1
sound, water
3
vertical arrow
2
R where lines are far apart, C
where lines are close together
4
horizontal arrow
Spread 3.2
A
B
A
햲 Hertz 햳 wavelength 햴 amplitude 햵 frequency 햶 speed
햷 velocity.
1
(a) amplitude, (b) wavelength
2
wavelength
3
0.5 Hz
Spread 3.3
A
B
A
햲 Focus 햳 concave 햴 convex 햵 converge 햶 diverge 햷 wavefront
햸 plane 햹 pulse 햺 ripple tank 햻 stroboscope.
1
(a) concave, (b) X at origin of
waves, (c) diverge
2
circle
Spread 3.4+3.5
A
B
A
햲 Normal 햳 incident ray 햴 reflected ray 햵 glancing angle 햶 diffuse
햷 echo 햸 reverberation 햹 refraction.
1
(a) N on normal, (b) I on ray
travelling towards mirror,
(c) R on reflected ray, (d) G at
angle between incident ray
and mirror
2
(a) N on normal, (b) ray
deviated towards normal,
(c) refraction
Spread 3.6+3.7
A
B
햲 Image 햳 real image 햴 virtual image 햵 diffraction 햶 real depth
햷 apparent depth 햸 no-parallax.
1
pinhole camera, overhead
projector
2
(a) at fish, (b) at end of virtual
ray above fish
3
behind the pointer
113
M
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Physics TB4
Topic help answers
TB4 Using waves
A
Spread 4.1
A
B
A
1
red
2
pink, orange, purple
3
microwave
4
300 000 000m/s,
300 000km/s
5
fluorescent
6
screen
5
four hours → factor 20, one
hour → factor5, three hours
→ factor 15, two hours →
factor 10
Spread 4.2
A
B
A
햲 Thermistor 햳 thermograph.
1
glows red
2
infrared
3
ultraviolet
4
electric bar fire, night sights,
remote control for hi-fi unit
Spread 4.3
A
B
A
햲 Aerial 햳 satellite 햴 gamma ray 햵 X-rays 햶 radio 햷 microwave
햸 radar 햹 ionosphere.
1
long – 2 km, medium –
200 m, micro – 2 mm,
short – 2 m
2
X-ray
Spread 4.4
A
B
햲 Endoscope 햳 optical fibre 햴 prism 햵 total internal
reflection 햶 digital signal 햷 critical angle.
1
top two traces
2
(a) total internal reflection,
o
(b) reflected through 90 at I,
exit block normally,
(c) normal, angle of
incidence, prism
3
optical fibre
2
sea bed, shoal of fish,
submarine, sunken wreck
Spread 4.5
A
A
B
114
햲 Ultraviolet 햳 infrared 햴 X-rays 햵 spectrum 햶 fluorescent
햷 radio 햸 visible light.
햲 Ultrasound 햳 sonar.
1
bat, dolphin, rat
M
?
Physics TB5
A
Topic help answers
Spread 4.7
A
B
A
햲 Magma 햳 lava 햴 volcanic ash 햵 core 햶 crust 햷 mantle
햸 lithosphere 햹 continental drift.
1
crust, mantle, core
2
volcanic ash, lava
Spread 4.8
A
B
햲 Asthenosphere 햳 metamorphism 햴 plate 햵 sea-floor spreading
햶 constructive boundary 햷 destructive boundary 햸 subduction
zone 햹 trench.
1
sea-floor spreading
2
earthquakes
TB5 Radioactivity
A
Spread 5.1
A
B
햲 Alpha particle 햳 beta particle 햴 gamma ray 햵 isotope
햶 radioisotope 햷 antineutrino 햸 atomic number 햹 mass number
햺 background radiation.
1
2
A
3
(a) alpha, (b) decreases by 4
4
(a) beta, (b) no change
Spread 5.2
A
B
A
(a) A=3 Z=6, (b) A=8 Z=14,
(c) A=6 Z=14
햲 Spark counter 햳 film badge 햴 Geiger-Müller tube 햵 ionisation,
radiation.
1
alpha
4
gamma
2
gamma
5
do not ionise air enough
3
beta
6
alpha
Spread 5.3
A
B
햲 Decay 햳 parent nuclide 햴 daughter nuclide 햵 half-life 햶 activity
햷 becquerel.
1
four hours
2
(a) radium-226, (b) radon-222
3
100 bq
115
M
?
Physics TB6
Topic help answers
Spread 5.4+5.5
A
햲 Bacteria 햳 cancer 햴 sterilise 햵 radiocarbon dating 햶 tracer.
B
A
1
gamma
5
gamma
2
beta
6
carbon-14
3
gamma
7
4
alpha
emits alpha radiation and has
a long half-life
Spread 5.6
A
B
햲 Radiation sickness 햳 radiation burns 햴 DNA 햵 lymphocyte
햶 mutation 햷 cumulative.
1
deoxyribonucleic acid
3
shielding
2
sixteen
4
radioactivity
TB6 The Earth and Universe
A
Spread 6.1
A
B
A
A
arrow from S towards centre
of E
2
closer to Earth
햲 Black hole 햳 nuclear fusion 햴 protostar 햵 white dwarf 햶 neutron
star 햷 red giant 햸 blue supergiant 햹 black dwarf 햺 nebulae
햻 supernova.
1
(a) hydrogen, (b) helium
2
gravity
3
white dwarf, red giant, red
supergiant
4
small star
Spread 6.3
A
B
116
1
Spread 6.2
B
A
햲 Centripetal 햳 gravity 햴 satellite 햵 planet 햶 asteroid 햷 comet
햸 Solar System 햹 polar orbit 햺 geo-stationary orbit.
햲 Quasar 햳 Big Bang 햴 Big Crunch 햵 red shift 햶 Doppler effect.
1
nothing
4
blue, towards
2
G4
5
towards
3
more than 12 billion years
M
?
Physics TB7
Topic help answers
TB7 Using electricity
A
Spread 7.1
A
B
A
A
A
3
negative
2
same number of protons as
electrons
4
induction
햲 Toner 햳 photocopier 햴 precipitator 햵 inert 햶 fuel 햷 lightning.
1
(a) negative, (b) positive
3
2
good conductor to prevent a
build up of charge
insulator, conductor,
lightning
4
A
햲 Coulomb 햳 electron 햴 ion 햵 charge 햶 conventional current.
1
(a) anticlockwise arrow,
(b) clockwise arrow
2
negative
Spread 7.4
A
B
A
(a) negative, (b) positive
Spread 7.3
B
A
1
Spread 7.2
B
A
햲 Proton 햳 neutron 햴 electron 햵 nucleus 햶 charge 햷 conductor
햸 insulator 햹 van de Graaff generator 햺 repel friction.
햲 Live 햳 neutral 햴 earth 햵 fuse 햶 watt 햷 alternating current
햸 direct current.
1
brown, blue, green and
yellow
2
13A
3
bulb lights and ammeter
vibrates
Spread 7.5+7.6
A
B
햲 Double insulation 햳 electric shock 햴 kilowatt-hour 햵 short
circuit 햶 circuit breaker 햷 residual current device.
1
double insulated
3
earth, current, live fuse
2
(a) 6, (b) 42p
4
Ticks next to all three
statements
TB8 Electromagnetism
A
Spread 8.1+8.2
A
햲 Motor 햳 Fleming’s left-hand rule 햴 radial field 햵 iron core
햶 split-ring commutator 햷 loudspeaker.
117
M
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Physics TB8
Topic help answers
B
A
A
A
A
A
1
B
2
(a) 0A, (b) increase turns,
increase strength of magnet,
move magnet
햲 Dynamo 햳 alternator 햴 mutual induction 햵 slip rings.
1
(a) 0A,
(b) needle deflects then
returns to zero,
(c) needle deflects opposite
way then returns to zero,
(d) increased
햲 Primary 햳 secondary 햴 step-up 햵 step-down 햶 laminated
햷 eddy current.
1
(a) secondary coil, iron core,
(b) step-up, (c) transformers
only work if the voltage is
a.c.
햲 Global warming 햳 pollution 햴 acid rain 햵 exciter 햶 superheated
steam 햷 renewable energy 햸 power station.
1
coal-burning, gas-burning,
oil-fired
5
kills trees and fish, for
example
2
hydroelectric
6
3
nuclear
geothermal, solar, tide, wind,
wave
4
dissolves rock
Spread 8.7
A
B
118
햲 Fleming’s right-hand rule 햳 Faraday’s Law 햴 induced current
햵 induced voltage.
Spread 8.6
B
A
C
increase distance between
magnetic poles
Spread 8.5
B
A
2
3
Spread 8.4
B
A
downwards
Spread 8.3
B
A
1
햲 Power loss 햳 National Grid 햴 transmission 햶 substation.
1
(a) step-up, (b) step-down
2
current, heat, current
M
T
?
Physics TB1
Self-assessment TB1 Foundation
Electric circuits
1
1
3
5
6
Solve the clues and fill in the squares with the electrical words.
Energy source.
2 Connection of electrical components.
Same current in these resistors.
4 Usually different current in these resistors.
Work done in taking current through component.
Electrical quantity with greek symbol.
7 Used to measure current.
1
2
3
4
5
6
7
C
U
R
R
E
N
T
2
Rearrange the letters in this anagram to make voltage
proportional to current.
3
Finish this sentence.
SLOW HAM
A device whose resistance changes with temperature is called a _ _ _ _ _ _ _ _ _
4
True or false?
The resistance of a wire increases as its length increases.
The current in a wire increases as its length increases.
Thick iron wire has a higher resistance than the same length of
thin iron wire.
5
Match the components to their voltage current graphs.
V
Bulb
I
V
Diode
I
V
Resistor
I
119
M
A
?
Physics TB1
Self-assessment answers TB1 Foundation
Electric circuits
1
1
3
5
6
Solve the clues and fill in the squares with the electrical words.
Energy source.
2 Connection of electrical components.
Same current in these resistors.
4 Usually different current in these resistors.
Work done in taking current through component.
Electrical quantity with greek symbol.
7 Used to measure current.
1
2
C
I
R
S
4
P
5
V O L T A
6
R E S I S T
7
A M M
3
2
3
C
E
A
G
A
E
C
U
R
R
E
N
T
E
I
I
A
L L
T
E S
L L E L
C E
E R
Rearrange the letters in this anagram to make voltage
proportional to current.
SLOW HAM
OHM’S LAW
A device whose resistance changes with temperature is called a thermistor.
4
5
True or false?
The resistance of a wire increases as its length increases.
T
The current in a wire increases as its length increases.
F
Thick iron wire has a higher resistance than the same length of
thin iron wire.
F
Match the components to their voltage current graphs.
V
Bulb
I
V
Diode
I
V
Resistor
I
120
M
T
?
Physics TB1
Self-assessment TB1 Higher
Electric circuits
Solve the clues and fill in the squares with electrical words.
1
Current particle.
Circuit flower.
Rotator.
Measures voltage.
1
3
5
7
2
4
6
8
Temperature dependent device.
Illuminating device.
Impedes current.
One way device.
1
2
3
4
5
6
7
8
Rearrange the letters in this anagram to make poor electrical
current passage.
2
NOT RUDE COMICS
3
A device which emits light when a current passes through it in
one particular direction is called a
_____
________
_____
True or false?
4
The resistance of an LDR increases as the light
intensity increases.
The resistance of a thermistor increases as the
temperature increases.
The resistance of a wire increases as its temperature
increases.
Arrange the ammeter readings in this circuit in order starting
with the lowest.
5
A1
10 Ω
A2
1Ω
A4
20 Ω
A3
200 Ω
A5
121
M
A
?
Physics TB1
Self-assessment answers TB1 Higher
Electric circuits
Solve the clues and fill in the squares with electrical words.
1
Current particle.
Circuit flower.
Rotator.
Measures voltage.
1
3
5
7
1
2
4
6
8
E L E C T R O N
2
T H E R
3
C H A R G E
4
L A M
5
M O T O
6
R E S I S
7
V O
8
D I O D E
Temperature dependent device.
Illuminating device.
Impedes current.
One way device.
M I S T O R
P
R
T O R
L T M E T E R
Rearrange the letters in this anagram to make poor electrical
current passage.
2
NOT RUDE COMICS
SEMICONDUCTOR
3
A device which emits light when a current passes through it in
one particular direction is called a
light emitting diode.
True or false?
4
The resistance of an LDR increases as the light
intensity increases.
F
The resistance of a thermistor increases as the
temperature increases.
F
The resistance of a wire increases as its temperature
increases.
T
Arrange the ammeter readings in this circuit in order starting
with the lowest.
5
3
A1
5
10 Ω
A2
1Ω
A4
20 Ω
A3
200 Ω
A5
2
122
4
1
M
T
?
Physics TB2
Forces and energy
1
Solve the clues and fill in the squares with the types of forces.
Find the name of a scientist
1
3
5
A turning force at a distance.
Vertical force acting on a mass.
Force between surfaces.
2
4
6
Equal and opposite to an action.
Force which causes 3.
Force in a stretched spring.
1
2
3
4
5
6
2
Rearrange the letters in this anagram to make something which
is stored.
TEEN GIRL EAT PONY
3
4
Draw a straight line from each quantity to its correct unit.
Write in the symbols for each unit. One has been done for you.
Acceleration
Joule
Energy
Metre per second
Power
Metre per second squared
Thrust
Newton
Torque
Newton metre
Velocity
Watt
N
Finish these sentences.
A poor conductor is known as an _ _ _ _ _ _ _ _ _.
Energy from the Sun reaches us by the process of _ _ _ _ _ _ _ _ _.
Energy is transferred through fluids by the process of _ _ _ _ _ _ _ _ _ _.
5
True or false?
The gradient of a velocity time graph gives the speed of
a body.
The distance travelled by a body is the area under a
velocity time graph.
A straight line distance time graph means the body is
accelerating.
Displacement is a vector and distance is a scalar.
A body needs a force acting on it before it will
accelerate.
123
M
A
?
Physics TB2
Forces and energy
1
Solve the clues and fill in the squares with the types of forces.
NEWTON
Find the name of the scientist.
1
3
5
A turning force at a distance.
Vertical force acting on a mass.
Force between surfaces.
2
4
6
Equal and opposite to an action.
Force which causes 3.
Force in a stretched spring.
1
M O M E N T
2
R E A C T I O N
3
W E I G H T
4
G R A V I T Y
5
F R I C T I O N
6
T E N S I O N
2
Rearrange the letters in this anagram to make something which
is stored.
TEEN GIRL EAT PONY
3
4
POTENTIAL ENERGY
Write in the symbols for each unit. One has been done for you.
Acceleration
Joule
Energy
Metre per second
m/s
Power
Metre per second squared
m/s2
Thrust
Newton
Torque
Newton metre
Velocity
Watt
J
N
Nm
W
A poor conductor is known as an insulator.
Energy from the Sun reaches us by the process of radiation.
Energy is transferred through fluids by the process of convection.
5
True or false?
The gradient of a velocity time graph gives the speed of
a body.
F
The distance travelled by a body is the area under a
velocity time graph.
T
A straight line distance time graph means the body is
accelerating.
F
Displacement is a vector and distance is a scalar.
T
A body needs a force acting on it before it will
accelerate.
T
124
M
T
?
Physics TB2
Forces and energy
1
1
2
3
4
5
6
7
2
Solve the clues and fill in the squares with the mechanical words.
Which three are not vectors?
Rate of motion in a
straight line.
Rate of motion.
How far a body has
moved.
The action of moving
faster.
Causes 4.
Needed for work to be
done.
The amount of material
in a body.
1
2
3
4
5
6
7
V
E
C
T
O
R
S
Rearrange the letters in this anagram to make a weight-to-mass ratio.
VISIT EARTH AND FORGETTING ALL
3
The part of a car which collapses on impact is called
the _ _ _ _ _ _ _
_ _ _ _.
This helps to reduce the _ _ _ _ _ _ _ _ _ _ _ _ on the occupants
by increasing the time to stop.
4
True or false?
A falling body loses gravitational potential energy and
gains kinetic energy.
The total energy of a falling body remains constant.
The temperature of water at the bottom of a waterfall
is lower than at the top.
Some machines can be 100% efficient.
A small amount of energy from the Sun reaches Earth
by convection.
5
Arrange the following in order of force needed to move the
object, starting with the smallest.
A 5 kg mass of lead falling at a constant velocity through thick
treacle.
A 2 kg bag of sugar with an acceleration of 1.5 m/s2 across a
smooth surface.
A 500 g jar of jam with an acceleration of 8 m/s2 with an
opposing frictional force of 2 N.
A 100 g apple with an acceleration of 10 m/s2 falling freely
under gravity.
125
M
A
?
Physics TB2
Forces and energy
1
1
2
3
4
5
6
7
2
Which three are not vectors? SPEED ENERGY MASS
Rate of motion in a
straight line.
Rate of motion.
How far a body has
moved.
The action of moving
faster.
Causes 4.
Needed for work to be
done.
The amount of material
in a body.
1
2
S P E
3
D I S P L A
4
A C C E L E R A
5
F
6
E N E
7
M A S
the
crumple zone.
This helps to reduce the deceleration on the occupants by
increasing the time to stop.
5
L O C
I
T Y
M E N T
O N
C E
Y
GRAVITATIONAL FIELD STRENGTH
The part of a car which collapses on impact is called
4
E
D
E
I
R
G
Rearrange the letters in this anagram to make a weight-to-mass ratio.
VISIT EARTH AND FORGETTING ALL
3
V
E
C
T
O
R
S
True or false?
A falling body loses gravitational potential energy and
gains kinetic energy.
T
The total energy of a falling body remains constant.
T
The temperature of water at the bottom of a waterfall
is lower than the top.
F
Some machines can be 100% efficient.
F
A small amount of energy from the Sun reaches Earth
by convection.
F
Arrange the following in order of force needed to move the
object, starting with the smallest.
A 5 kg mass of lead falling at a constant velocity through thick
treacle. – 1
2
A 2 kg bag of sugar with an acceleration of 1.5 m/s across a
smooth surface. – 3
2
A 500 g jar of jam with an acceleration of 8 m/s with an
opposing frictional force of 2 N. – 4
2
A 100 g apple with an acceleration of 10 m/s falling freely
under gravity. – 2
126
M
T
?
Physics TB3
Wave properties
1
1
3
5
Solve the clues and fill in the squares with the properties of
images.
Cannot be projected onto a screen.
Can be projected onto a screen.
Upside down.
1
2
4
6
Larger.
The same way up.
Smaller.
I
M
A
G
E
S
2
3
4
5
6
2
Rearrange the letters in this anagram to make two types of
waves.
VALS TRAIN RENT IS LONG DUE
3
4
Match each word with its description.
amplitude
distance between two peaks of a wave
frequency
maximum displacement from rest
speed
number of waves passing a point in one second
wavelength
how fast the wave is moving
When a wave spreads out after passing through a gap this is
known as _ _ _ _ _ _ _ _ _ _ _.
5
True or false?
The angle of incidence always equals the angle of
reflection.
The angle of incidence is always less than or equal to
the angle of refraction.
A normal ray is one at 180° to the surface.
A ray of light entering a glass block along the normal is
not refracted.
Multiple reflections of sound are call reverberations.
6
Arrange the following in order of speed, starting with the
slowest.
light wave
sound wave
water wave
127
M
A
?
Physics TB3
Wave properties
1
Solve the clues and fill in the squares with the properties of
images.
Cannot be projected onto a screen.
Can be projected onto a screen.
Upside down.
1
3
5
1
3
R
U P R
5
I N
I M I N
4
6
D
2
V I
2
M
E A
I G
V E
I S
R
A
L
H
R
H
4
Larger.
The same way up.
Smaller.
T U A L
G N I F
I
E D
T
T E D
E D
Rearrange the letters in this anagram to make two types of
waves.
VALS TRAIN RENT IS LONG DUE
3
2
4
6
TRANSVERSE
LONGITUDINAL
Match each word with its description.
amplitude
distance between two peaks of a wave
frequency
maximum displacement from rest
speed
number of waves passing a point in one second
wavelength
how fast the wave is moving
When a wave spreads out after passing through a gap this is
known as diffraction.
5
6
True or false?
The angle of incidence always equals the angle of
reflection.
T
The angle of incidence is always less than or equal to
the angle of refraction.
F
A normal ray is one at 180° to the surface.
F
A ray of light entering a glass block along the normal is
not refracted.
T
Multiple reflections of sound are call reverberations.
T
slowest.
light wave – 3
sound wave –
2
water wave – 1
128
M
T
?
Physics TB3
Wave properties
1
All of the answers end in ION.
I
I
I
I
I
I
I
Which ION is another word meaning oscillation?
Which ION bounces back from a surface?
Which ION spreads out through a gap?
Which ION changes direction at a boundary?
Which ION is squeezed longitudinally?
Which ION is a continuous echo?
Which ION is stretched out longitudinally?
2
O
O
O
O
O
O
O
N
N
N
N
N
N
N
Rearrange the letters in this anagram to make two depths.
LEAP NEAR TRAP
3
4
Write in the symbols for each unit.
frequency
hertz
velocity
metre
wavelength
metre per second
Waves transfer _ _ _ _ _ _ from one place to another without
transferring _ _ _ _ _ _.
5
True or false?
Plane waves incident at a concave barrier diverge after
reflection.
Plane waves incident at a straight barrier obey the laws
of reflection.
Curved waves incident at a straight barrier are
reflected as straight waves.
When waves enter a shallower region of water the
wave speed decreases.
Water waves spread out if the size of gap and
wavelength are the same.
6
Arrange the following in order of speed, starting with the slowest.
a sound wave in air of frequency 110 Hz and wavelength 3.0 m
a sound wave in aluminium of frequency 500 Hz and
wavelength 12.8 m
a sound wave in concrete of frequency 250 Hz and wavelength
20.0 m
a sound wave in steel of frequency 50 Hz and wavelength
120.0 m
a sound wave in water of frequency 1 kHz and wavelength 1.5 m
129
M
A
?
Physics TB3
Wave properties
1
Which ION is another word meaning oscillation?
Which ION bounces back from a surface?
Which ION spreads out througha gap?
D
Which ION changes direction at a boundary?
Which ION is squeezed longitudinally?
C
Which ION is a continuous echo?
R E V
Which ION is stretched out longitudinally?
R
2
4
REAL
frequency
hertz
velocity
metre
wavelength
metre per second
R
E
A
A
E
R
A
APPARENT
Hz
m
m/s
transferring
6
B
L
R
R
R
E
F
Write in the symbols for each unit.
energy
matter.
Waves transfer
5
I
F
F
F
P
B
E
Rearrange the letters in this anagram to make two depths.
LEAP NEAR TRAP
3
R
I
R
O
E
A
V
E
F
E
M
R
R
from one place to another without
True or false?
Plane waves incident at a concave barrier diverge after
reflection.
F
Plane waves incident at a straight barrier obey the laws
of reflection.
T
Curved waves incident at a straight barrier are
reflected as straight waves.
F
When waves enter a shallower region of water the
wave speed decreases.
T
Water waves spread out if the size of gap and
wavelength are the same.
T
Arrange the following in order of speed, starting with the slowest.
a sound wave in air of frequency 110 Hz and wavelength 3.0 m –
1
a sound wave in aluminium of frequency 500 Hz and wavelength
12.8 m – 5
a sound wave in concrete of frequency 250 Hz and wavelength
20.0 m – 3
a sound wave in steel of frequency 50 Hz and wavelength 120.0 m –
a sound wave in water of frequency 1 kHz and wavelength 1.5 m –
130
2
4
A
C
C
C
S
A
C
T
T
T
T
S
T
T
I
I
I
I
I
I
I
O
O
O
O
O
O
O
N
N
N
N
N
N
N
M
T
?
Physics TB4
Using waves
1
1
3
5
7
Solve the clues and fill in the squares with the types of waves.
What word reads vertically?
They detect broken bones.
Used in remote control devices.
Causes a nice tan.
Beyond human hearing.
2
4
6
8
Used by Newton to make a rainbow.
Cook or send messages with this wave.
Longest electromagnetic wave.
Very penetrating.
1
2
3
4
5
6
7
8
2
Rearrange the letters in this anagram to make a light
transmitter.
CABLE IS PROFIT
3
Which two parts of the Earth form the lithosphere?
crust
4
inner core
outer core
outer mantle
The angle at which light leaving a more dense material is reflected
instead of refracted is known as the _ _ _ _ _ _ _ _ angle.
5
True or false?
All electromagnetic waves are transverse waves.
No light is emitted from fluorescent materials.
An endoscope works because of total internal
refraction.
Lava comes from the molten core of the Earth.
Red flames are hotter than blue flames.
6
Arrange the following in order of wavelength, starting with the
shortest.
blue
gamma
microwave
red
ultraviolet
yellow
131
M
A
?
Physics TB4
Using waves
1
1
3
5
7
Solve the clues and fill in the squares with the types of waves.
What word reads vertically? SPECTRUM
They detect broken bones.
Used in remote control devices.
Causes a nice tan.
Beyond human hearing.
Used by Newton to make a rainbow.
Cook or send messages with this wave.
Longest electromagnetic wave.
Very penetrating.
2
4
6
8
1
X R A Y S
2
P
3
I N F R A R E
4
M I C
5
U L T
6
R
7
U L T R A S O U
8
G A M
2
O W A V E
A V I O L E T
D I O
D
A
OPTICAL FIBRES
Which two parts of the Earth form the lithosphere?
crust
4
I S M
Rearrange the letters in this anagram to make a light
transmitter.
CABLE IS PROFIT
3
R
D
R
R
A
N
M
inner core
outer core
outer mantle
The angle at which light leaving a more dense material is reflected
instead of refracted is known as the critical angle.
5
6
True or false?
All electromagnetic waves are transverse waves.
T
No light is emitted from fluorescent materials.
F
An endoscope works because of total internal
refraction.
F
Lava comes from the molten core of the Earth.
F
Red flames are hotter than blue flames.
F
Arrange the following in order of wavelength, starting with the
shortest.
blue –
3
red – 5
132
gamma –
1
ultraviolet –
microwave –
2
yellow –
4
6
M
T
?
Physics TB4
Using waves
1
1
3
5
7
9
Solve the clues and fill in the squares with seismic and Earth structure words.
Why is the vertical word not a good place to be?
Transverse earthquake wave.
Detect earth vibrations.
The outer parts of the Earth.
Fracture of rock.
The Earth’s central region.
2
4
6
8
This travels through the centre of the Earth.
The origin of an earthquake.
The major part of the Earth.
Thin surface layer.
1
2
3
4
5
6
7
8
9
2
Rearrange the letters in this anagram to make land movement.
CANNOT FIND LITTER
3
Which two travel at the same speed? Put rings around the
correct answers.
p waves
4
radio waves
s waves
visible light
An area where the oceanic plate descends beneath the
continental plate is known as a _ _ _ _ _ _ _ _ _ _ _ _ _ _.
The increased temperature and pressure can cause
_ _ _ _ _ _ _ _ _ _ _ _ producing new rocks by recrystallisation.
5
True or false?
The boundaries between colliding plates are
destructive plate boundaries.
Lithosphere is destroyed at constructive and
The rate of sea-floor spreading is about two to three
millimetres per year.
New crust is formed from magma when two plates are
moving apart.
A trench forms when the continental plate moves up
over the oceanic plate.
133
M
A
?
Physics TB4
Using waves
1
Solve the clues and fill in the squares with seismic and Earth
structure words. Why is the vertical word not a good place to
be? EPICENTRE
– The place on the Earth’s surface
immediately above the origin of an earthquake.
Transverse earthquake wave.
Detect earth vibrations.
The outer parts of the Earth.
Fracture of rock.
The Earth’s central region.
1
3
5
7
9
2
4
6
8
This travels through the centre of the Earth.
The origin of an earthquake.
The major part of the Earth.
Thin surface layer.
1
5
L
2
I
S W A V E
2
P
3
S E I
4
F O C
T H O S P H E
6
M A N
7
F A U L T
8
C R
9
C O R E
U S T
CONTINENTAL DRIFT
Which two travel at the same speed? Put rings around the
correct answers.
p waves
4
A V E
M O M E T E R
S
E
L E
Rearrange the letters in this anagram to make land movement.
CANNOT FIND LITTER
3
W
S
U
R
T
radio waves
s waves
visible light
An area where the oceanic plate descends beneath the
continental plate is known as a subduction
zone.
The increased temperature and pressure can cause
metamorphism producing new rocks by recrystallisation.
5
True or false?
The boundaries between colliding plates are
T
Lithosphere is destroyed at constructive and
F
The rate of sea-floor spreading is about two to three
millimetres per year.
F
New crust is formed from magma when two plates are
moving apart.
T
A trench forms when the continental plate moves up
over the oceanic plate.
T
134
M
T
?
Physics TB5
Radioactivity
1
1
3
5
7
Solve the clues and fill in the squares with the names of seven
particles. Which particle reads vertically?
A type of atom.
A positive particle.
A neutral particle.
Radioactive electron.
2
4
6
The centre of an atom.
A negative particle.
Helium nucleus.
1
2
3
4
5
6
7
2
Rearrange the letters in this anagram to make the surnames of
two nuclear scientists.
EEC CLUB REQUIRE
3
Which two things detect radioactivity? Put rings around the
correct answers.
film badge
4
seismometer
spark counter
thermometer
When a radioisotope emits radiation and changes into another
isotope this is known as radioactive _ _ _ _ _.
5
Arrange the following in order of mass, starting with the lightest.
alpha particle
hydrogen atom
6
beta particle
proton
True or false?
The mass number is the total number of protons and
neutrons
The atomic number is the number of neutrons
Isotopes of an element have the same atomic number
When an isotope emits an alpha particle, its mass
increases by four
7
Which type of radiation is used for each job?
smoke detector
thickness measurement of aluminium sheet
sterilising food
135
M
A
?
Physics TB5
Radioactivity
1
Solve the clues and fill in the squares with the names of seven
particles. Which particle reads vertically? ISOTOPE
A type of atom.
A positive particle.
A neutral particle.
Radioactive electron.
1
3
5
7
1
2
N U C
N U C L E
3
P
4
E L E
5
N E U T
6
A
L
U
R
C
R
L
7
B
2
4
6
I
S
O
T
O
P
E
The centre of an atom.
A negative particle.
Helium nucleus.
D E
T
R
N
H
T
O N
O N
A
A
2
Rearrange the letters in this anagram to make the surnames of
two nuclear scientists.
EEC CLUB REQUIRE
CURIE BECQUEREL
3
Which two things detect radioactivity? Put rings around the
correct answers.
film badge
4
seismometer
spark counter
thermometer
When a radioisotope emits radiation and changes into another
isotope this is known as radioactive decay.
5
Arrange the following in order of mass, starting with the lightest.
alpha particle – 4
hydrogen atom – 3
6
7
beta particle –
proton – 2
1
True or false?
The mass number is the total number of protons and
neutrons
T
The atomic number is the number of neutrons
F
Isotopes of an element have the same atomic number
T
When an isotope emits an alpha particle, its mass
increases by four
F
Which type of radiation is used for each job?
smoke detector
α
thickness measurement of aluminium sheet
γ
sterilising food
γ
136
M
T
?
Physics TB5
Radioactivity
1
Fill in the squares with safety precautions.
1
D
E
C
A
Y
2
3
4
5
2
Rearrange the letters in this anagram to find something which
is always around us.
DIG OUT ROCK AND A BRAIN
3
Which two particles have the same mass? Put rings around the
correct answers.
alpha particle
4
beta particle
helium nucleus
proton
When radiation passes through a material, the atoms of the
material have electrons removed causing them to be
_ _ _ _ _ _ _ _ _ _ charged.
This process is known as _ _ _ _ _ _ _ _ _ _.
5
Draw a straight line from each radioactive decay to its product.
226
88
241
95
241
98
218
84
24
11
14
6
6
Ra decays by the emission of an alpha particle to form
Am decays by the emission of an alpha particle to form
Cf decays by the emission of an alpha particle to form
Po decays by the emission of a beta particle to form
Na decays by the emission of a beta particle to form
C decays by the emission of a beta particle to form
218
85
237
93
24
12
14
7
237
96
222
86
At
Cm
Mg
N
Np
Rn
The uses are correct, but are the reasons true or false?
241
95
Am is used in smoke detectors because it has a
short half life.
60
27
Co is used for cancer treatment because it is very
penetrating.
14
12
C is used to date artefacts because it is not very
penetrating.
241
95
Am is used in a canning plant because it is very
penetrating.
7
A radioactive material has a mass of 150 g. What is the total
mass of material after three half lives have passed? Put a ring
150 g
75 g
37.5 g
18.75 g
137
M
A
?
Physics TB5
Radioactivity
1
Fill in the squares with safety precautions.
1
I E L D I N G
T I M E
3
D I R E C T I O N
4
D I S T A N C E
5
A C T I V I T Y
S H
2
2
Rearrange the letters in this anagram to find something which
is always around us.
DIG OUT ROCK AND A BRAIN
3
Which two particles have the same mass? Put rings around the
correct answers.
alpha particle
4
BACKGROUND RADIATION
beta particle
helium nucleus
proton
When radiation passes through a material, the atoms of the
material have electrons removed causing them to be
positively charged.
This process is known as ionisation.
5
Draw a straight line from each radioactive decay to its product.
226
88
241
95
241
98
218
84
24
11
14
6
6
Ra decays by the emission of an alpha particle to form
Am decays by the emission of an alpha particle to form
Cf decays by the emission of an alpha particle to form
Po decays by the emission of a beta particle to form
Na decays by the emission of a beta particle to form
C decays by the emission of a beta particle to form
85
237
93
24
12
14
7
237
96
222
86
At
Cm
Mg
N
Np
Rn
The uses are correct, but are the reasons true or false?
241
95
Am is used in smoke detectors because it has a
short half life.
60
27
Co is used for cancer treatment because it is very
penetrating.
14
12
C is used to date artefacts because it is not very
penetrating.
241
95
Am is used in a canning plant because it is very
penetrating.
7
218
F
T
F
T
A radioactive material has a mass of 150 g. What is the total
mass of material after three half lives have passed? Put a ring
150 g
138
75 g
37.5 g
18.75 g
M
T
?
Physics TB6
1
Finish filling in the squares with the names of six planets.
Which planet reads vertically?
1
J
2
3
S
4
5
U
L
6
2
Rearrange the letters in this anagram to make two planets.
TEEN HUNT PEAR
3
Which two things orbit Earth? Put rings around the correct
answers.
asteroid
4
comet
moon
satellite
The name of the force which keeps the planets in orbit around
the Sun is _ _ _ _ _ _ _.
5
6
Arrange the following in order of size, starting with the
smallest.
comet
galaxy
planet
solar system
star
universe
True or false?
An object in geo-stationary orbit takes 12 hours to
orbit the Earth.
An object in geo-stationary orbit never passes over the
poles.
A centrifugal force keeps things moving in a circle.
Objects closer to Earth travel faster in their orbit.
7
8
Put the phases of the life cycle of a star in the right order.
adult star
blue supergiant
nebulae
protostar
red supergiant
supernova
We know that the Universe is expanding because
of _ _ _ _ _ _ _ _. Choose from
red eye
red giant
red light
red shift
139
M
A
?
Physics TB6
1
Finish filling in the squares with the names of six planets.
Which planet reads vertically? URANUS
1
J
M E
3
M
4
V E
5
P L
2
2
U
R
A
N
U
6
S
P
C
R
U
T
A
I T E R
U R Y
S
S
O
T U R N
Rearrange the letters in this anagram to make two planets.
EARTH
TEEN HUNT PEAR
3
Which two things orbit Earth? Put rings around the correct
answers.
asteroid
4
NEPTUNE
comet
moon
satellite
The name of the force which keeps the planets in orbit around
the Sun is gravity.
5
Arrange the following in order of size, starting with the
smallest.
comet – 1
galaxy
–2
star – 3
solar system
–4
universe – 6
planet
6
7
8
–5
True or false?
An object in geo-stationary orbit takes 12 hours to
orbit the Earth.
F
An object in geo-stationary orbit never passes over the
poles.
T
A centrifugal force keeps things moving in a circle.
F
Objects closer to Earth travel faster in their orbit.
T
Put the phases of the life cycle of a star in the right order.
adult star – 3
blue supergiant – 4
nebulae – 1
protostar – 2
red supergiant – 5
supernova – 6
We know that the Universe is expanding because of red
Choose from
red eye
140
red giant
red light
red shift
shift.
M
T
?
Physics TB6
1
1
3
5
7
9
Solve the clues and fill in the squares with universal bodies and effects.
A cloud of gas and dust.
2
A most distant visible object.
4
A cold, dead star.
6
Rock between Mars and Jupiter. 8
Sputnik was the first man-made one.
1
2
3
5
7
8
9
2
Effect causing frequency shift.
A cloud of dust and ice.
Astronomer who gave his name to a telescope.
One of nine in solar orbit.
B
L
A
4
C
K
6
H
O
L
E
Rearrange the letters in this anagram to make two galaxies.
MANDY WAKE DIM ROYAL
3
Which space body is the odd one out and why? Put a ring
neutron
4
red giant
supernova
white dwarf
The Universe is believed to have begun with a large explosion
known as the _ _ _ _ _ _ _.
5
slowest.
GOES weather satellite in orbit 36 000 km above the Earth
Hubble Space telescope in orbit 600 km above the Earth
International Space Station in orbit 390 km above the Earth
NOAA weather satellite in orbit 830 km above the Earth
6
True or false?
A galaxy moving away from us appears redder than
usual.
The faster a galaxy is moving, the smaller the amount
of red shift.
The age of the Universe is estimated to be at least
twelve billion years.
The end of the Universe will be the big crunch.
141
M
A
?
Physics TB6
1
1
3
5
7
9
Solve the clues and fill in the squares with universal bodies and effects.
A cloud of gas and dust.
2
A most distant visible object.
4
A cold, dead star.
6
Rock between Mars and Jupiter. 8
Sputnik was the first man-made one.
1
N E B U
D O P P L E
3
Q U A S
4
C O
5
B L A C K D
6
H U
7
A S T E R O I
8
P L A
9
S A T E L
2
2
L
R
A
M
W
B
D
N
L
R
E T
A R F
B L E
E T
I T E
MILKY WAY
ANDROMEDA
Which space body is the odd one out and why? Put a ring
neutron
4
A
Rearrange the letters in this anagram to make two galaxies.
MANDY WAKE DIM ROYAL
3
Effect causing frequency shift.
A cloud of dust and ice.
Astronomer who gave his name to a telescope.
One of nine in solar orbit.
red giant
supernova
white dwarf
It is not a type of star.
The Universe is believed to have begun with a large explosion
known as the big
5
bang.
slowest.
GOES weather satellite in orbit 36 000 km above the Earth – 1
Hubble Space telescope in orbit 600 km above the Earth – 3
International Space Station in orbit 390 km above the Earth – 4
NOAA weather satellite in orbit 830 km above the Earth – 2
6
True or false?
A galaxy moving away from us appears redder than
usual.
T
The faster a galaxy is moving, the smaller the amount
of red shift.
F
The age of the Universe is estimated to be at least
twelve billion years.
T
The end of the Universe will be the big crunch.
F
142
M
T
?
Physics TB7
Using electricity
1
1
3
5
7
Solve the clues and fill in the squares with the electrical
quantities or properties. What wire reads vertically?
A charged particle.
Unit of charge.
Rate of using energy.
The brown wire.
2
4
6
Protect from high 4.
A flow of charge.
The safety wire.
1
2
3
4
5
6
7
2
Rearrange the letters in this anagram to make electrical energy.
WAIT RUTH – LOOK
3
Which two devices work because of electrostatics?
ink jet printer
4
light bulb
photocopier
transformer
If an object loses electrons, it becomes _ _ _ _ _ _ _ _ _ _
charged.
5
True or false?
Like charges attract
Power = voltage ÷ current.
The electrical supply from the mains is alternating
current.
An RCD detects a small current change between the
earth and neutral wires.
A double insulated device does not have an earth wire.
6
Arrange the following in order of energy usage, starting with
the lowest.
60 W bulb used for 4 hours
100 W computer for 1 hour
1 kW iron for 10 minutes
2.5 kW kettle for 3 minutes
3 kW fire for 1 hour
143
M
A
?
Physics TB7
Using electricity
1
1
3
5
7
Solve the clues and fill in the squares with the electrical
quantities or properties. What wire reads vertically? NEUTRAL
A charged particle.
Unit of charge.
Rate of using energy.
The brown wire.
1
I
F U
3
C
4
C U R R E
5
P O W
2
2
O
S
O
N
E
6
E
2
4
6
N
E
U L O M B
T
R
A R T H
7
L I V E
Rearrange the letters in this anagram to make electrical energy.
WAIT RUTH – LOOK
3
Protect from high 4.
A flow of charge.
The safety wire.
KILOWATT – HOUR
Which two devices work because of electrostatics?
ink jet printer
4
light bulb
photocopier
transformer
If an object loses electrons, it becomes positively
charged.
5
6
True or false?
Like charges attract
F
Power = voltage ÷ current.
F
The electrical supply from the mains is alternating
current.
T
An RCD detects a small current change between the
earth and neutral wires.
F
A double insulated device does not have an earth wire.
T
Arrange the following in order of energy usage, starting with
the lowest.
60 W bulb used for 4 hours – 4
100 W computer for 1 hour – 1
1 kW iron for 10 minutes – 3
2.5 kW kettle for 3 minutes – 2
3 kW fire for 1 hour – 5
144
M
T
?
Physics TB7
Using electricity
1
I
I
I
I
I
Which ION causes charging by rubbing?
Which ION makes unlike charges move together?
Which ION makes like charges move apart?
Which ION allows electrons to move through a metal?
Which ION causes opposite charges by contact?
2
O
O
O
O
O
N
N
N
N
N
Rearrange the letters in this anagram to make shocking piece of
equipment.
RAT OF FEARED VEGAN GRAN
3
Which two wires are connected to the ground either at the
house or at the power station? Put rings around the correct
answers.
earth
4
5
fuse
live
neutral
Draw a straight line between the boxes to complete the
equations. Write the correct unit in the box next to the
quantity.
current =
charge ⫼ time
energy =
current × voltage
power =
power × time
voltage =
work done ⫼ charge passed
True or false?
It is important to connect an aircraft to its tanker
before refuelling.
Oil tankers are filled with hydrogen gas before cleaning
to avoid explosions.
Air can become a conductor between high voltage
differences.
Electrons are conducted away from the inside of a
television screen.
Photocopiers work because positively charged toner is
attracted to paper.
6
Arrange the following in order of charge passed, starting with
the lowest.
A current of 2 A in a circuit for 5 minutes.
6 kJ of energy is transferred between two points with a voltage
difference of 12 V.
A current in a 3 Ω resistor with a voltage difference of 6 V
between its ends for 7 minutes.
A current of 10 A in a circuit for 30 s.
145
M
A
?
Physics TB7
Using electricity
1
Which ION causes charging by rubbing?
Which ION makes unlike charges move together?
Which ION makes like charges move apart?
Which ION allows electrons to move through a metal?
Which ION causes opposite charges by contact?
2
6
fuse
live
neutral
Draw a straight line between the boxes to complete the
equations. Write the correct unit in the box next to the
quantity.
amp
joule / kilowatt-hour
watt / kilowatt
volt
5
I
A
U
U
U
C
C
L
C
C
VAN DE GRAAFF GENERATOR
Which two wires are connected to the ground either at the
house or at the power station? Put rings around the correct
answers.
earth
4
R
R
P
D
D
Rearrange the letters in this anagram to make shocking piece of
equipment.
RAT OF FEARED VEGAN GRAN
3
F
A T T
R E
C O N
I N
current =
charge ⫼ time
energy =
current × voltage
power =
power × time
voltage =
work done ⫼ charge passed
True or false?
It is important to connect an aircraft to its tanker
before refuelling.
T
Oil tankers are filled with hydrogen gas before cleaning
to avoid explosions.
F
Air can become a conductor between high voltage
differences.
T
Electrons are conducted away from the inside of a
television screen.
T
Photocopiers work because positively charged toner is
attracted to paper.
F
Arrange the following in order of charge passed, starting with
the lowest.
A current of 2 A in a circuit for 5 minutes. –
3
6 kJ of energy is transferred between two points with a voltage
difference of 12 V. – 2
A current in a 3 Ω resistor with a voltage difference of 6 V
between its ends for 7 minutes. – 4
A current of 10 A in a circuit for 30 s. –
146
1
T
T
S
T
T
I
I
I
I
I
O
O
O
O
O
N
N
N
N
N
M
T
?
Physics TB8
Electromagnetism
1
1
2
3
4
5
6
7
2
Solve the clues and fill in the squares with electromagnetic words.
Find the name of a scientist.
He worked on
electromagnetism.
An electromagnetic sound
device.
An a.c. producer.
Reverses current in a motor.
National carrier of electricity.
The process of producing a
current from a changing
magnetic field.
A current producer.
1
2
3
4
5
6
7
Rearrange the letters in this anagram to make a larger voltage.
ROSE – START FERN PUMP
3
Which two are renewable energy sources used to produce
electricity? Put rings around the correct answers.
coal
4
oil
Sun
water
The input coil of a transformer is known as the _ _ _ _ _ _ _ coil
and the output coil is known as the _ _ _ _ _ _ _ _ _ coil.
5
True or false?
Fleming’s left hand rule works for motors.
A motor spins faster if the current is smaller.
A motor spins faster if the magnetic field is stronger.
Reversing the current and field directions will reverse
the motor direction.
If a d.c. motor is spun by hand, a direct current is
produced.
6
Draw a straight line between the boxes to match each finger
with the correct physical quantity for Fleming’s left hand rule.
First finger
Current direction
Second finger
Force on wire
Thumb
Magnetic field direction
147
M
A
?
Physics TB8
Electromagnetism
1
1
2
3
4
5
6
7
2
Solve the clues and fill in the squares with electromagnetic words.
Find the name of a scientist. FLEMING
He worked on
electromagnetism.
An electromagnetic sound
device.
An a.c. producer.
Reverses current in a motor.
National carrier of electricity.
The process of producing a
current from a changing
magnetic field.
A current producer.
3
A L T
4
C O
5
G R
6
I
A
O
R
M
D
D
E
R
U
N
U
A
D
A
T
oil
STEP-UP TRANSFORMER
Sun
water
The input coil of a transformer is known as the
primary coil and the output coil is known as the
secondary coil.
5
6
True or false?
Fleming’s left hand rule works for motors.
T
A motor spins faster if the current is smaller.
F
A motor spins faster if the magnetic field is stronger.
T
Reversing the current and field directions will reverse
the motor direction.
F
If a d.c. motor is spun by hand, a direct current is
produced.
T
Draw a straight line between the boxes to match each finger
with the correct physical quantity for Fleming’s left hand rule.
148
First finger
Current direction
Second finger
Force on wire
Thumb
Magnetic field direction
D
S
T
A
A
P
O
T
Y
E A K E R
R
O R
U C T I O N
N E R A T O R
Which two are renewable energy sources used to produce
electricity? Put rings around the correct answers.
coal
4
F
L
E
M
I
N
7
G
2
Rearrange the letters in this anagram to make a larger voltage.
ROSE – START FERN PUMP
3
1
M
T
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Physics TB8
Electromagnetism
1
Solve the clues and fill in the squares with transformer words.
1 This one increases voltage.
2 See 10.
3 The input side.
4 The output side.
5 This one decreases voltage.
6 A changing magnetic one makes it work.
7 Two of these, one each side.
8 Direct will not work. This will.
9 Thin sheeted core.
10 and 2 These cause the core to heat up.
11 With 100% efficiency, this is the same at
both input and output.
2
Rearrange the letters in this anagram to
make two opposite electromagnetic
devices.
1
2
3
4
7
8
9
11
NOT MY DOOR MA
3
T
R
A
N
5
S
6
F
O
R
M
10
E
R
The part of the motor which reverses the current direction is
known as the _ _ _ _ _ _ _ _ _ _.
4
True or false?
An a.c. generator has slip rings.
If a generator is turned faster, the size of the induced
current increases.
If a generator is turned faster, the frequency of the
current decreases.
Large generators have moving magnets and fixed coils.
Mutual induction is the induction of an opposing
voltage in the same coil.
5
Arrange the following transformers in order of output voltage,
starting with the lowest.
No. of input turns
Input in V
No. of output turns
500
230
500
5000
230
250
50
12
1000
2000
12
500
200
24
100
149
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Physics TB8
Electromagnetism
1
Solve the clues and fill in the squares with transformer words.
1 This one increases voltage.
2 See 10.
3 The input side.
4 The output side.
5 This one decreases voltage.
6 A changing magnetic one makes it work.
7 Two of these, one each side.
8 Direct will not work. This will.
9 Thin sheeted core.
10 and 2 These cause the core to heat up.
11 With 100% efficiency, this is the same at
both input and output.
2
Rearrange the letters in this anagram to
make two opposite electromagnetic
devices.
NOT MY DOOR MA
T
R
A
N
5
S
6
F
7
C O
8
A L T E R
9
L A M
10
E
11
P O W E R
1
S
2
C U
3
P R I M
4
S E C O
E
R
R
D
T
I
I
N
I
D
P
E
Y
A
E
E
L
A
N
D
U P
N T S
R
P
L
S
T
A
Y
Y
D O W N
D
I N G
T E D
MOTOR DYNAMO
3
The part of the motor which reverses the current direction is
known as the
4
5
commutator.
True or false?
An a.c. generator has slip rings.
T
If a generator is turned faster, the size of the induced
current increases.
T
If a generator is turned faster, the frequency of the
current decreases.
F
Large generators have moving magnets and fixed coils.
T
Mutual induction is the induction of an opposing
voltage in the same coil.
F
Arrange the following transformers in order of output voltage,
starting with the lowest.
150
No. of input turns
Input in V
No. of output turns
500
230
500
4
5000
230
250
2
50
12
1000
5
2000
12
500
1
200
24
100
3
M
T
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Physics TBA1
Self-assessment TBA1 Higher
1
1
Solve the clues and fill in the
squares with electronic components
and devices.
2
3
1 See 9.
2 Output 1 if either input 1.
3 Digital computational device.
4 Opposite output to input.
5 Temperature sensitive component.
6 Flip flop.
7 AND and not.
8 Two NORS with feedback.
9 and 1 Combinations of electronic
switches.
10 Switches high current with low.
2
4
5
6
7
8
9
10
Draw a straight line between the boxes to join each logic gate
with its symbol and truth table.
in
AND
0
0
1
1
out
0
1
0
1
in
NAND
0
0
1
1
out
0
1
0
1
in
NOR
0
0
1
1
OR
3
0
1
1
1
out
0
1
0
1
in
0
0
1
1
0
0
0
1
1
1
1
0
out
0
1
0
1
1
0
0
0
True or false?
A potential divider uses two resistors to split a current
in a circuit.
LDRs and thermistors can be used in potential divider
arrangements.
A relay is used because the output current from a logic
gate is too small.
Two NOR gates can be combined to make an AND
gate.
151
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A
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Physics TBA1
Self-assessment answers TBA1 Higher
1
Solve the clues and fill in the
squares with electronic components
and devices.
1 See 9.
2 Output 1 if either input 1.
3 Digital computational device.
4 Opposite output to input.
5 Temperature sensitive component.
6 Flip flop.
7 AND and not.
8 Two nors with feedback.
9 and 1 Combinations of electronic
switches.
10 Switches high current with low.
2
1
G A T
2
O R
3
C O M P U
4
N O T
5
T H
6
L A T
7
N A
8
B
9
L
10
R E
E S
T E R
E
C
N
I
O
L
M I
R
H
D
S
G
A
T A B L E
I C
Y
Draw a straight line between the boxes to join each logic gate
with its symbol and truth table.
in
0
0
1
1
AND
out
0
1
0
1
in
0
0
1
1
NAND
0
0
1
1
NOR
OR
True or false?
A potential divider uses two resistors to split a current
in a circuit.
F
LDRs and thermistors can be used in potential divider
arrangements.
T
A relay is used because the output current from a logic
gate is too small.
T
Two NOR gates can be combined to make an AND
gate.
F
152
0
1
1
1
out
0
1
0
1
in
0
0
1
1
0
0
0
1
out
0
1
0
1
in
3
S T O R
1
1
1
0
out
0
1
0
1
1
0
0
0
M
T
?
Physics TBA2
Processing waves
1
1
3
5
7
Solve the clues and fill in the squares with resonant phenomena.
Resonance at the natural one.
Wave which appears not to move.
Maximum amplitude.
Main.
1
2
4
5
6
7
8
9
2
4
6
8
9
Type of vibration.
A multiple.
How a particular note sounds.
External vibration.
Zero amplitude.
R
E
3
S
O
N
A
N
C
E
2
Rearrange the letters in this anagram to make two opposite
electromagnetic devices.
3
True or false?
I FACED NEXT RIVER
All colours of light have the same refractive index for
water.
Constructive interference occurs when waves are in
phase.
Beats occur if notes are always out of phase.
Open pipes have antinodes at both ends.
Interference can be explained by thinking of light as a
particle.
4
Draw four lines from each object position to the correct image
properties and position.
object position
image position / property
between lens and f
between lens and f
between f and 2f
at 2f
beyond 2f
between f and 2f
same side of lens as object
real
virtual
at 2f
magnified
diminished
same size
beyond 2f
upright
inverted
153
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Physics TBA2
Processing waves
1
1
3
5
7
Solve the clues and fill in the squares with resonant phenomena.
Resonance at the natural one.
Wave which appears not to move.
Maximum amplitude.
Main.
1
2
M
4
H A
8
9
2
F
N
F R
O D E
3
S
R M O
5
A N
6
Q U A
7
F U N
O R C
O D E
4
Type of vibration.
A multiple.
How a particular note sounds.
External vibration.
Zero amplitude.
E Q U E N C Y
T A T I O N A R Y
N I C
T I N O D E
L I T Y
D A M E N T A L
E D
Rearrange the letters in this anagram to make two opposite
electromagnetic devices.
I FACED NEXT RIVER
3
2
4
6
8
9
REFRACTIVE INDEX
True or false?
All colours of light have the same refractive index for
water.
F
Constructive interference occurs when waves are in
phase.
T
Beats occur if notes are always out of phase.
F
Open pipes have antinodes at both ends.
T
Interference can be explained by thinking of light as a
particle.
F
Draw four lines from each object position to the correct image
properties and position.
object position
image position / property
between lens and f
between lens and f
between f and 2f
at 2f
beyond 2f
between f and 2f
same side of lens as object
real
virtual
at 2f
magnified
diminished
same size
beyond 2f
upright
inverted
154
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T
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Physics TBA3
1
1 To move backwards.
2 Measured in Ns.
3 A thrown body.
4 and 7 Works by Newton
III (three words).
5 Path described by 3.
6 Forward force.
7 See 4.
1
2
4
5
6
7
2
I
M
3
P
U
L
S
E
Rearrange the letters in this anagram to make two things a
rocket needs to carry into space.
YOUNG EX-ELF
3
The amount of energy required to change the temperature of
unit mass of a substance by one degree is called the
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ of the substance.
4
Equations true or false?
momentum = mass × velocity
impulse = velocity / time
force = momentum change / time
u + at = √(u + 2as)
2
½ (u + v)t = ut + ½ at
5
2
Arrange the following in order of energy requirement starting with the
smallest.
Energy needed to raise the temperature of 0.5 kg of water (s.h.c. 4200 J/kgoC)
o
by 25 C.
Energy supplied to the element of a 230 V, 3 kW kettle heater in two
minutes.
Energy supplied to the 40% efficient lift motor which lifts 500 N to a height
of 60 m in 1minute.
6
Isaac and Helen are standing at the top of a 50 m high cliff. They have two
similar sized stones.
Helen drops her stone at the same time as Isaac throws his as hard as he can
horizontally away from the cliff.
Which stone hits the beach first. Put a ring around the correct answer.
Both stones together
Helen’s stone
Isaac’s stone
155
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Physics TBA3
1
1 To move backwards.
2 Measured in Ns.
3 A thrown body.
4 and 7 Works by Newton
III (three words).
5 Path described by 3.
6 Forward force.
7 See 4.
2
1
R E C O I
2
M O M
3
P
4
J E T T U
5
P A R A B O L
6
T H R U S
7
E N G I N E
Rearrange the letters in this anagram to make two things a
rocket needs to carry into space.
OXYGEN FUEL
YOUNG EX-ELF
3
L
E N T U M
R O J E C T
R B I N E
A
T
The amount of energy required to change the temperature of
unit mass of a substance by one degree is called the
4
of the substance.
Equations true or false?
momentum = mass × velocity
T
impulse = velocity / time
F
force = momentum change / time
T
u + at = √(u + 2as)
T
2
½ (u + v)t = ut + ½ at
5
2
T
Arrange the following in order of energy requirement starting with the
smallest.
Energy needed to raise the temperature of 0.5 kg of water (s.h.c. 4200 J/kgoC)
o
by 25 C. – 1
Energy supplied to the element of a 230 V, 3 kW kettle heater in two
minutes. – 3
Energy supplied to the 40% efficient lift motor which lifts 500 N to a height
of 60 m in 1minute. – 2
6
Isaac and Helen are standing at the top of a 50 m high cliff. They have two
similar sized stones.
Helen drops her stone at the same time as Isaac throws his as hard as he can
horizontally away from the cliff.
Which stone hits the beach first. Put a ring around the correct answer.
Both stones together
156
Helen’s stone
Isaac’s stone
I
L E
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Key Stage 3
Summary sheet
TB1 Electric circuits
The following circuit symbols are very important:
switch
or
cell
or
A
lamp
variable resistor
battery
ammeter
wire
Electricity is a flow of charged particles called electrons. This flow of
charged particles is called electrical current. The circuit must be complete
for this to happen. A switch enables the circuit to be broken in order to
stop the electric current. Current is measured in amps (A) using an
ammeter. The ammeter should be connected in series with other
components in the circuit. Current is not used up by the components in
the circuit.
A cell or battery provides an electric current that will travel around a
circuit. It transforms chemical energy into electrical energy. A battery is
simply a number of cells connected together with the poles pointing in the
same direction.
There are two basic types of circuit, series and parallel. Series circuits have
all the components arranged one after the other on a single loop of the
circuit (see Fig 1). The lamps in a series circuit will be dimmer and if one
lamp ‘burns out’ the others will not light either. In a series circuit, the
current is the same in all parts of the circuit. However, the cell or batteries
will last longer. An example of a series circuit is a set of Christmas tree
lights.
A parallel circuit has its components connected on separate loops of the
circuit (see Fig 2). The lamps in this type of circuit will be brighter and if
one lamp ‘burns out’ the others will stay lit. In a parallel circuit, the
current in the main branch is the sum of the currents in the side branches.
However, the cells or batteries will not last as long. An example of a
parallel circuit is the ring main in a house.
Fig 1
Wires will oppose the flow of current in a circuit, and this is called
resistance. It is this resistance that causes wires to heat up. A variable
resistor or dimmer can alter the resistance in a circuit, allowing more or
less current to pass through.
Nerves in the body are rather like electrical circuits, carrying messages
around the body from the brain and spinal cord.
Fig 2
157
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Key Stage 3
TB2 Forces and energy
All forces do three things: change the shape of an object, change its speed, or
change its direction. Forces are measured in newtons (N), using a forcemeter.
An object that is standing still will have balanced forces on it.
Upthrust is the upward force from water that keeps things afloat. Whether an
object will float or not depends on its density. A dense object will have particles
that are very close together, it is likely to sink. Objects with a density less than
water will float. An object weighed in water will weigh less than in air. This is
because of upthrust.
Mass is the amount of matter that makes up an object. It is measured in grams
and kilograms. Weight is the force of gravity pulling on a mass. Weight is a
force and so is measured in newtons. On Earth, each kilogram of mass weighs
10 newtons.
Friction is the force that opposes motion and is caused by surfaces rubbing
together. Friction can be useful or it can be a nuisance. Adding a lubricant, like
oil or grease, to the working parts of machines can reduce friction. They reduce
friction by smoothing out the rough surfaces.
It is the frictional forces that make a car stop. The faster a car is travelling, the
longer its stopping distance will be.
Temperature is a measure of how hot things are. In science, the Celsius scale
(°C) is used. Temperature is measured using a thermometer.
Heat is a form of energy. If an object absorbs heat energy, then its temperature
will rise. If it loses heat energy, then its temperature will fall.
A material that will allow heat energy to flow through it more easily is called a
good thermal conductor, e.g. metals. A material that is a poor thermal
conductor will allow heat energy to flow less easily, e.g. wool, polystyrene, and
rubber. Liquids and gases are also poor thermal conductors. Poor thermal
conductors are called insulators. Energy flow through a material is called
conduction. Conduction is the transfer of heat energy from particle to particle
by vibration.
Trapped air is a particularly good insulator. This method of insulation is used
in duvet fillings, expanded polystyrene, and loft insulation. Trapped air stops
energy being lost by convection. Convection relies on air being able to flow and
trapped air cannot, so convection stops. Energy costs money and so insulators
are used throughout homes in an effort to reduce unwanted energy transfer,
e.g. double glazing, draught excluders, heavy curtains, carpets.
When objects get hotter they get bigger. This is called expansion. For example,
roads are often made of concrete slabs. On a hot day they will expand, so
between the slabs are expansion gaps filled with a soft material, which allows
the slabs to expand easily.
Liquids and gases are called fluids because they can flow. When liquids and
gases expand the particles get further apart, and this causes a decrease in
density. When this happens the hot, less dense fluids will rise to be replaced by
cooler, denser fluids. This is called convection current.
Whilst conduction and convection both need particles to carry energy, thermal
radiation does not. Thermal radiation is part of the electromagnetic spectrum.
In particular, the part called infrared. This is the only type of energy transfer
that can occur in a vacuum. Heat and light from the Sun travels as infrared
radiation through the vacuum of space.
158
Summary sheet
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Key Stage 3
Summary sheet
Solids, liquids and gases are all states of matter. They can change from one
state to another if heat energy is given or taken away. These changes are
reversible.
In order to calculate the speed of an object, the distance it has travelled and the
time taken must be known. Usually the speed calculated is an average speed,
because over a journey, a moving object, e.g., a car, will change its speed at
various points. Speed is measured in metres/second (m/s) or kilometres/second
(km/s). The process of increasing speed is called accelerating and slowing down
is decelerating.
speed =
distance
time
Objects move as the result of exerting a force upon them. A force can also
produce a change in speed. In general, the larger the force, the greater the effect it
will have on speed. The forward force is called thrust and the opposing force is
caused by the frictional effect from the surface and air resistance, often referred
to as drag. These are called the horizontal forces. If thrust and drag are balanced
then the object will move at a constant speed. The vertical forces are weight and
upthrust. When forces are balanced then there will be no change in speed.
Air and water resistance increase with increasing speed. Therefore, if the resisting
force increases, then the energy required to move the object forward at a greater
speed will be more. For example, the fuel consumption of a car will increase with
increasing speed. Streamlining can reduce the effects of air resistance or water
resistance. Streamlining is where the shape of the moving object (car, boat, plane)
is modified so that the fluid (air, water) flows over it smoothly and this will enable
the object to move faster without the need to increase thrust.
Air resistance is a form of friction, which is caused by two surfaces rubbing
together. When this happens, heat is produced. If air resistance increases with
increasing speed, then at very high speeds the air resistance can lead to heating.
With falling objects, the two main forces are air resistance and weight. As an
object falls, weight remains the same, but air resistance will increase as the
object accelerates. Eventually, as the object falls, the forces of air resistance and
weight will balance and the object will fall at a constant speed.
Pressure depends on two things, the amount of force exerted and the area over
2
2
which it is distributed. Pressure is measured in newtons/metre (N/m ) or
2
2
newtons/cm (N/cm ). Practical examples of this effect are everywhere.
For example, a sharp blade will have the force spread over a small area, so the
pressure will be great, and this will make it better for cutting.
pressure =
force
area
Gases and liquids can also be under pressure. Pneumatics is the practical
application of gases under pressure, hydraulics is the practical application of
liquids under pressure. Because there are many empty spaces between gas
particles, they can be compressed, e.g. make the particles come closer together
by using a force. However, there are no spaces between liquid particles so they
are incompressible; this makes them excellent at transmitting the force
throughout the liquid.
Atmospheric or, underwater pressure at a particular point depends on the
weight of fluid above.
A lever is a simple machine which uses a pivot. Machines can be either used as
force multipliers (crowbar or wheelbarrow), or as distance multipliers (arm or
fishing rod). If a smaller effort force is exerted than the load force, then the
lever will be a force magnifier. The further away the effort force is from the
pivot, then the more the force is magnified. Because there is a pivot involved
the force will have what is known as a turning effect or moment or torque.
Moments are measured in newton metres (Nm). Levers are found in many
everyday objects, such as scissors and tin openers. Arms and legs are also levers.
159
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Key Stage 3
TB3 Wave properties
Light travels from a luminous source. Light is a wave. A luminous object
is one that gives off its own light, including stars, candles, light bulbs,
lasers etc. Light travels much faster than sound. The speed of light is
300 000 km/s and it takes about 8.5 seconds to travel from the Sun to the
Earth. We can see non-luminous objects because light is reflected off them
into our eyes.
Light travels in straight lines. It does not bend around objects. In science,
drawing rays can represent the path of light. A beam of light is several rays
travelling together.
Light cannot bend around opaque objects. However, the direction of light
can be changed in two ways. One is by reflection and the other is by
refraction. Refraction is where the light changes direction at the boundary
between two different media, e.g. as it travels from air into glass or water.
All sounds begin with an initial vibration. Sound is a wave. For example,
the strings of a guitar vibrate to produce sound. Sounds can be high or low,
loud or quiet, hard or soft. How high or low a sound is refers to its pitch or
frequency. Loud or soft refers to a sound’s intensity, and loud or quiet
refers to the sound’s quality. A ‘picture’ of a sound wave can be seen if a
signal generator is connected to an oscilloscope.
The height of a wave indicates how loud it will be. The higher the wave
the louder the sound. The height of a wave is referred to as the wave’s
amplitude.
Sound waves need a medium to travel through. They can travel through
solids, liquids and gases, but they do so at different speeds. Sound travels
fastest through solids (5000 m/s through iron) and slowest through gases
(330 m/s through air). Sound travels faster through solids because they are
denser than gases and liquids. The particles are closer together and so pass
on the vibrations more efficiently. Sound cannot travel through a vacuum
because there are no particles to vibrate.
160
Summary sheet
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Key Stage 3
Summary sheet
TB4 Using waves
When light hits an object, the result will depend on the material of the
object, which can be transparent, translucent or opaque. Transparent
objects will allow most of the light to be transmitted through them.
Translucent objects will allow less transmission and opaque objects will
allow no transmission of light. The light that is not transmitted may be
absorbed or reflected.
When light is reflected from a plane (flat) surface, its path can be predicted.
The light is reflected from a surface at the same angle at which it hits it.
This is the Law of Reflection. Reflections are very useful in everyday life, for
example, in mirrors, reflective clothing and periscopes.
When light is reflected from a plane surface, for example, a mirror, an
image is formed. The image is formed as far behind the mirror as the object
is in front. It is upright but it is laterally inverted. Laterally inverted means
that right is left and left is right. The image formed in a plane mirror is
virtual. Virtual means that the image cannot be formed on a screen.
If white light is passed through a prism at the right angle, it can be
dispersed into seven different colours, which are called the visible
spectrum (red, orange, yellow, green, blue, indigo, and violet).
Coloured filters will transmit their own colour, but will absorb all the
other colours of the spectrum. For example, a green filter will allow green
light through but will absorb all other colours. The primary colours of light
are red, green and blue. When they are all mixed together, they form white
light. Mixing any two together will form a new colour. For example,
mixing red and blue light together will form magenta.
A coloured object in white light will reflect its own colour and absorb all other
colours. Black is complete absorption of light by an object. For example, a red
object in green light will appear black because it will absorb the green light.
Pitch or frequency of sound can be altered in several ways. For example, a
stringed instrument will produce a sound of higher pitch if the string is
shortened, tightened, or made lighter. Wind instruments will produce a
sound of higher pitch if the pipe is shorter. A drum will produce a sound of
higher pitch if the skin is tightened. These actions all have the effect of
increasing the speed of the vibration, e.g. a higher frequency of vibration.
All animals do not hear the same range of frequencies of sound. Some
animals can detect sounds that are inaudible (can’t be heard) to human ears.
For example, humans cannot hear a dog whistle or hear the ultrasonic beeps
sent out by bats to find their location. In fact, different people will hear
different ranges of pitch and these ranges will change as people age.
The typical range of hearing for an adult human is from 20 Hz to 20 000 Hz.
Sound waves are picked up by the ear and travel into the ear canal to the
eardrum, which vibrates. This causes the small bones to vibrate and the
vibration is passed to the inner ear, where the vibrations are converted into
electrical signals and translated by the brain into sounds.
Any sound that is unpleasant is referred to as noise. When this noise is frequent
or carries on all day (like airport noise), it is referred to as noise pollution. Noise
levels can be measured using a sound-level meter in units called decibels (dB).
Workers in very noisy factories may have to wear ear defenders to protect their
ears from the noise. These act as sound insulators. Loud noise can permanently
affect hearing by damaging the sensitive nerve endings in the inner ear.
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TB5 Radioactivity
There are no KS3 statements on radioactivity. You will, however, need to
know something about atomic structure before you start to study
radioactivity.
You may have done this in Chemistry.
All substances are made up from about 100 elements.
These elements are made up from very tiny particles called atoms.
A piece of copper is made up from copper atoms and a piece of carbon is
made up from carbon atoms. Atoms are made up from different numbers of
three particles – protons, neutrons and electrons. Protons have a mass of
one atomic mass unit (a.m.u.) and a single positive charge. Electrons have
negligible mass and a single negative charge. Neutrons have a mass of one
a.m.u. but no charge.
As all atoms are neutral, they must contain equal numbers of protons and
electrons.
An atom contains protons and neutrons packed together in a positively
charged nucleus. Electrons move around the nucleus in certain energy
levels or shells. Each energy level can contain a maximum number of
electrons.
E.g. A sodium-23 atom contains 11 protons, 11 electrons and 12 neutrons.
The protons and neutrons are packed together in the nucleus. The
electrons are arranged in three energy levels – two in the first energy level,
eight in the second energy level and one in the third energy level.
It is possible to get different atoms of the same element. These must
contain the same number of protons and electrons but different numbers of
neutrons. These different atoms are called isotopes.
E.g. A carbon-12 atom has 6 protons, 6 neutrons and 6 electrons. A
carbon-14 atom has 6 protons, 8 neutrons and 6 electrons.
Radioactivity involves changes in the nucleus of an atom.
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Key Stage 3
Summary sheet
TB6 The Earth and Universe
A day is the time it takes for a planet to make one complete rotation on its
axis. For Earth this is 24 hours. In daytime the Earth is facing the Sun and at
night it is facing away. A year is the time taken for a planet to make one
complete orbit around the Sun, 365 days for the Earth. The Moon is a natural
satellite of the Earth, which means that it is in orbit around the Earth. A month
is the time taken for the Moon to go through all of its phases (or shapes). These
phases are always in the same order. A lunar month is 28 days long.
The Sun is our local star. A star is a luminous object, which means that it gives
off its own light. Moons and planets are non-luminous. The Sun’s light
illuminates them and they can be seen by this reflected light.
Eclipses only happen when the Sun, the Earth and the Moon are all in a line.
There are two types, the lunar eclipse and the solar eclipse. A lunar eclipse is
an eclipse of the Moon. It happens when the Earth is positioned between the
Sun and the Moon. Because the Moon is so much smaller than the Earth, the
Earth will cast a shadow over the Moon and it will be in darkness. A solar
eclipse is an eclipse of the Sun. This time the Moon will cast a shadow over the
Earth, but because it is so much smaller than the Earth, only a relatively small
part of the Earth is in darkness.
The seasons are caused by the tilt of the Earth on its axis, which is 23.5°. In
summer, the Earth is tilted towards the Sun, giving warmer, longer days and the
Sun appears to be high in the sky. In winter, the Earth is tilted away from the
Sun, giving colder, shorter days and the Sun always appears to be low in the sky.
The Sun, together with all the planets, asteroids and their satellites in orbit
around it make up the Solar System. Within our solar system, only the Earth is
known to support any life forms because the conditions are right, e.g. the right
temperature, oxygen present, water present. The planets are kept in orbit by
gravitational forces. The orbits of the planets are not exactly circular, but they
are ellipses or oval shaped.
Looking from Earth, the stars appear to be moving. However, this is because of
the Earth’s rotation. The stars can only be seen at night because the Sun is
closer and is therefore much brighter. A collection of stars in a pattern is called
a constellation. Many millions of stars clustered together are called a galaxy.
All the galaxies put together form the universe.
Gravity is an attractive force which acts on the Earth towards the centre of the
planet. The greater the mass of an object, the greater will be its gravitational
force. It is the force of gravity acting upon the mass of an object that gives it
weight. This means that say, on the Moon, which has a lesser mass than Earth,
the gravitational force will be less and therefore objects will weigh less.
Gravitational force between objects also decreases as the distance between
them increases. For example, to enable a rocket to get off the ground a thrust
force is needed that is greater than the rocket’s weight, but once in space,
further away from the gravitational force, less thrust is needed.
Early models of the solar system put the Earth at the centre, with the Sun and
other planets orbiting around it (Ptolemy). However, Copernicus discovered
that it is actually the Sun that is at the centre, and that the Earth and other
planets orbit around it. The Sun is the most massive object in our solar system
and therefore it has the most gravity, which keeps all the planets in orbit
around it. Compared to the Moon, the Earth is more massive and it is the
Earth’s gravity that keeps the Moon in orbit around it. The Moon is said to be a
natural satellite of the Earth.
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Key Stage 3
TB7 Using electricity
Fuses are deliberate weak links in a circuit, designed to melt if there is too
big a current. They melt because the electrical energy from the battery is
transformed into heat and light. They are used to protect appliances from a
large and possibly damaging current. For this reason it is important always
to use the correct fuse for the job. Household fuses have been replaced by
electromagnetic circuit breakers, which are resettable when they ‘trip’ out.
Electricity can be dangerous. Mains electricity (which comes to homes) has a
high voltage (230 V). This is a much greater voltage than can be supplied from
batteries. For this reason, electrical appliances should not be handled with wet
hands, wires should not be frayed or objects inserted into plug sockets.
Electricity can cause severe burns or electrocution if these hazards are ignored.
Energy can be taken in many forms and can be routinely converted from
one form into another. Some examples are potential energy (stored energy),
kinetic energy (movement energy), sound energy, solar (light) energy,
thermal (heat) energy, chemical energy and electrical energy, to mention
but a few. Electrical energy is used so widely because it is easily converted
into other types by energy changing devices, e.g. a kettle converts
electrical energy into heat energy.
The electrical energy in a circuit can be transformed (converted) in the
components, e.g. to produce light, sound, movement, etc. Cells and
batteries store chemical energy which is converted into electrical energy.
Electrical energy cannot be stored easily.
Voltmeters are used to measure voltage (also known as potential
difference) in the circuit. The measurements can be for certain
components in the circuit, which, if added together, will give the total
voltage of the cell or battery. These measurements indicate how much
energy is being transferred by a component.
The National Grid system transfers energy from the power station to the
home at high voltages but low current. This is less wasteful. Transformers
can easily change the voltage to suit requirements.
In the home, electrical current is conducted from ‘the mains’ to components
in electrical circuits and these convert the energy into other useful forms.
Circuits that are involved in heating (kettles, electric fires), will transfer
energy at a greater rate than others (hi-fi systems, computers). The rate of
energy transfer is known as power and is measured in watts (W). Mains
electricity is supplied by a generator back at the power station. A variety of
energy resources can be used to generate electricity such as nuclear, fossil
fuels, and renewable energy sources such as wave or wind power.
The major problem with using fossil fuels as energy resources is that they
produce pollution and contribute to the Greenhouse Effect, whilst nuclear
power stations produce dangerous and difficult to deal with waste.
However, renewable sources, although ‘clean’, have other problems.
For instance, wind turbines are unsightly and noisy, building dams for
hydroelectric power can affect the ecology and are not viable in flat areas.
In any energy transfer, there is a transfer to useful energy and ‘wasted’
energy. This wasted energy is said to have been dissipated or spread out
and cannot be used again. This wasted energy is usually heat energy.
For example, in a coal burning power station a great deal of energy
(about 70%) is wasted in the boiler or in the cooling water.
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Key Stage 3
Summary sheet
TB8 Electromagnetism
Magnets will attract magnetic materials – iron, cobalt, and nickel.
All other metals cannot be magnetised. A compound called magnetic iron
oxide can also be magnetised. This is not a metal but is used in ceramic
magnets. Magnets have north-seeking and south-seeking poles. Like poles
of magnets will repel, unlike poles of magnets will attract. Magnetic forces
will act through non-magnetic materials. For example, a fridge magnet will
attract the steel door of the fridge even though a piece of paper is in
between.
Magnetic materials can be made into magnets in several ways. One way is
to ‘stroke’ the material with the pole of another magnet in the same
direction. This lines up the magnetic domains of the material being
‘stroked’.
A magnetic field is the area in which a magnetic force can be felt or
experienced. The magnetic field of a magnet can be shown by using iron
filings and has a distinctive shape. When magnetic fields are drawn, field
line patterns are used. The field lines are closer together at the poles
which tells us that the poles are where the magnetic field is strongest.
The further away from the magnet you go, the weaker the magnetic field
becomes. The direction of a magnetic field can be plotted using compasses
and this can be shown by arrows on the magnetic field lines.
The Earth has a magnetic field. A compass needle is simply a free-moving
magnet that will line up with the Earth’s magnetic field. In order for a
compass needle to point north, the point at which it is suspended, the
pivot must be almost free of friction and air resistance.
When an electric current is passed down a wire, a magnetic field is
produced around it. The magnetic field can be made stronger by wrapping a
coil of wire around a ‘soft’ iron core. Magnetically ‘soft’ means that the
iron can be both magnetised and demagnetised easily. This type of magnet
is called an electromagnet. The field can be made even stronger by using
more coils of wire or a larger current. If the iron bar is made into a
horseshoe shape, the field will be stronger because the poles are closer
together. The magnetic field around an electromagnet is the same shape as
that of a bar magnet.
Because the core is magnetically ’soft’, it will become magnetised only
when there is a current flowing in the coil. This makes an electromagnet
very useful in picking things up and putting them down when needed.
Electromagnets are found in scrapyards to pick cars up and in electric bells
and relays.
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Physics TB1
Student checklist
Electric circuits
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on those
statements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can:
1
A
identify cells, batteries and generators as electrical sources, and bulbs, resistors, bells,
motors, LEDs and buzzers as parts of an electrical circuit where electrical energy is
dissipated.
recognise the electrical symbols for a cell, battery, power supply, filament bulb, switch,
LDR, fixed and variable resistor, LED, motor, heater, ammeter and voltmeter should be
known.
2
recall that resistors are heated when electric current passes through them.
3
describe the effect of a variable resistor in controlling the brightness of a lamp and the
speed of a motor.
explain the effect of a variable resistor in controlling the brightness of a lamp and the
speed of a motor.
4
measure resistance by correctly placing a voltmeter and an ammeter in a circuit.
5
state the equation V = IR.
use the equation V = IR
6
describe how current varies with voltage in a metal wire at constant temperature.
describe how current varies with voltage in a filament bulb.
describe how current varies with voltage in a silicon diode.
7
describe how the resistance of an LDR varies with light level.
8
describe how the resistance of a thermistor varies with temperature.
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B
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Physics TB2
Student checklist
Forces and energy
I can:
A
B
Force and Rotation
1
explain how the turning effect of a force depends on the size of the force and the
perpendicular distance from the point of application to the pivot.
2
state the equation moment of a force = force × perpendicular distance to pivot.
use this equation.
3
use, for a balanced system, the equation
sum of clockwise moments = sum of anticlockwise moments.
Force and Energy
4
state the equation work done = force × distance moved in its own direction.
use this equation.
5
use the equation power = work done (or energy transfer) / time taken.
6
use the equation
change in gravitational
= mass potential energy
7
state the equation kinetic energy =
1
2
gravitational
height moved.
field strength
mv2.
use this equation.
8
state the equation energy transferred = work done.
use this equation
9
use the equation
energy efficiency =
10
useful energy output
total energy input
explain the meaning of the term energy efficiency in the heating of buildings.
explain the meaning of the term energy efficiency in the performance of machines.
11
describe how domestic insulation reduces energy transfer by conduction, convection and
radiation.
12
use data on energy efficiency measures to evaluate cost-effectiveness of different
approaches.
Force and Motion
13
state the equation speed = distance / time taken.
use this equation.
14
plot and interpret distance–time graphs.
15
calculate speed from a distance–time graph.
16
plot and interpret speed time–graphs.
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Physics TB2
Student checklist
I can:
A
17
calculate distance travelled from a speed–time graph.
18
describe how braking distance is affected by the road surface, the mass and speed of the
vehicle.
19
describe factors that affect the “thinking distance”.
20
recall that stopping distance is the sum of the thinking distance and the braking distance.
21
use the equation, energy transferred = force × distance =
to discuss stopping distances.
22
recall that velocity describes the speed and direction of a moving object.
23
calculate velocity from a displacement–time graph.
24
state the equation,
acceleration =
1
2
mv2.
change in velocity
.
time taken
use this equation.
25
calculate acceleration from a velocity–time graph.
26
describe the relative sizes of the horizontal forces on an object moving in a straight line
when it is accelerating.
when it is decelerating.
when it is moving at constant speed.
27
state the equation force = mass × acceleration.
use this equation.
28
apply this relationship to the action of seat-belts and crumple zones.
29
describe forces acting between objects.
30
recognise that when object A pulls or pushes object B then object B pulls or pushes
object A with an equal-sized force in the opposite direction.
Forces on falling objects
31
describe the effects of the Earth’s pull and resistive forces due to motion in a fluid.
32
use the equation: weight = mass × gravitational field strength.
33
explain how the size of the resistive force depends on the speed of the object.
34
describe how the forces acting on an object falling at terminal velocity are balanced.
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B
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Physics TB3
Student checklist
Wave properties
I can:
A
1
describe the effects of absorbing electromagnetic waves: heating, ionisation and damage
to cells and tissue.
2
explain that wave motion involves an oscillation.
3
describe the differences between a transverse and a longitudinal wave.
B
give an example of a transverse wave.
give an example of a longitudinal wave.
4
recall the meaning of the term frequency.
recall the meaning of the term wavelength.
recall the meaning of the term amplitude.
5
identify the wavelength transverse wave.
identify the amplitude of a transverse wave.
6
describe the effect on the loudness of a sound when the amplitude is changed.
7
describe the effect on the pitch of a sound when the frequency is changed.
8
state the equation, wave speed = frequency × wavelength.
use this equation.
9
describe how echoes are caused by the reflection of sound.
10
recall that refraction involves the change in speed of a wave.
11
explain how changing the speed of a wave causes a change in wavelength.
explain how changing the speed of a wave may cause it to change direction.
12
explain and illustrate how virtual images are caused by the refraction of light.
13
recall that water waves can be reflected at a plane barrier.
recall that the angle of incidence equals the angle of reflection.
14
explain and illustrate how plane waves are reflected at a concave barrier.
explain how circular ripples are reflected at a plane barrier.
15
recall that water waves can be refracted if they are slowed down.
16
recall that water waves can spread out at a narrow gap.
recall that this is known as diffraction.
17
describe how the amount of spreading depends on the size of the gap compared to the
wavelength of the wave.
18
recall that light can be diffracted but needs a very small gap as the wavelength of light is
very small.
19
appreciate that the diffraction of light is evidence for the wave nature of light.
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Physics TB3
Student checklist
I can:
A
20
explain that sound can be diffracted.
21
describe how the amount of diffraction of sound depends on the size of the sound source.
describe how the amount of diffraction of sound depends on the wavelength of the sound.
170
B
M
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Physics TB4
Student checklist
Using waves
I can:
A
B
The Electromagnetic Spectrum
1
recall that the different types of electromagnetic waves form a continuous spectrum with
a range of wavelength and frequency and that they transfer energy at the same speed in
free space.
2
list the parts of the spectrum in order of wavelength and frequency (gamma rays; X-rays;
ultraviolet; light; infra-red; microwaves; radio waves).
3
recall that microwaves cause heating when absorbed by water.
recall that microwaves cause burns when absorbed by body tissue.
4
recall that infra-red radiation causes heating when absorbed by any object, and its use in
radiant heaters.
5
recall that ultra-violet radiation is produced in fluorescent lights.
6
recall that being out in the Sun for too long can cause sunburn and skin cancer from the
ultra-violet radiation.
7
explain that the darker the skin, the more ultra-violet radiation is absorbed by the skin
and less reaches the deeper body tissues to cause these cells to become cancerous.
8
describe how information can be transmitted using electromagnetic radiation, including
the use of satellites for global communication.
9
explain that radio waves are readily diffracted and are therefore suitable for broadcasting.
10
explain how information in narrow beams can be transmitted using microwaves.
11
describe the use of infra-red radiation in night photography.
12
describe what happens to light incident on a perspex/glass-air surface both above and
below the critical angle of incidence.
13
describe how light is reflected at the inner face of a right-angled prism.
14
explain how optical fibres are used in endoscopy.
15
explain how optical fibres allow the rapid transmission of data using digital signals.
16
describe the transmission of data pulses using light in optical fibres.
17
describe the difference between analogue and digital signals.
18
describe the advantage of using digital signals to allow more information to be
transmitted.
19
explain that X-rays pass through flesh but are absorbed by bone.
20
list the safety precautions that should be taken when using X-rays and gamma-rays.
21
interpret information about the development of ideas concerning the dangers involved
with using X-rays and/or radioactive substances from given information.
22
describe the use of gamma-rays as tracers to detect malfunction of organs and as
treatment for killing body tissue.
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Physics TB4
Student checklist
I can:
A
23
recall that ultrasound is a high-frequency longitudinal wave.
24
explain how distances can be measured using echo-sounding.
25
explain how the reflection of ultrasound by body tissue enables organs to be scanned.
26
describe how ultrasound is used for pre-natal scanning.
27
describe one non-medical use of ultrasound.
Seismic Waves
28
recall that earthquakes produce shock waves, that affect the surface of the Earth and
travel inside the Earth.
recall that these shock waves can be detected by instruments (seismometers) located on
the Earth’s surface.
29
recall that during earthquakes, P-waves (primary waves) are formed.
recall that P-waves are longitudinal waves which travel through both solids and liquids.
recall that S-waves (secondary waves) are formed.
recall that S-waves are transverse waves which travel through solids but not through
liquids.
recall that P-waves travel faster than S-waves.
30
explain how the differences in behaviour of P-waves and S-waves inside the Earth can be
interpreted in terms of a simple mantle/core structure for the inner Earth.
31
explain how the seismographic record can be used to find the speed of seismic waves,
which give evidence for the structure of the Earth.
32
describe the composition of the Earth’s outermost layer in terms of plates in relative
motion.
recall that new plate material is formed at mid-ocean ridges where sea-floor spreading
occurs.
recall that plates collide at subduction zones where the oceanic lithosphere descends
below the continental lithosphere, forming off-shore trenches and parallel volcanic
mountain chains.
recall that plates slide past each other at transform fault zones.
recall that the forces at the plate boundaries contribute to the rock cycle.
recall that sea floor spreading causes fractures (cracks) which are filled with molten rock
from below the lithosphere (new rock is produced).
recall that at subduction zones, increased temperature and pressure can cause
metamorphism.
recall that metamorphism produces new rocks by recrystallisation (no melting occurs).
recall that descending lithosphere enters the hot mantle and partially melts to form
magma.
recall that rising magma can crystallise deep below the surface to form coarse-grained
rocks (e.g. granite) or rise to the surface in volcanoes to form fine-grained rocks (e.g. basalt
lava or volcanic ash).
33
172
interpret given information about developments in ideas of plate tectonics from given
information.
B
M
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Physics TB5
Student checklist
Radioactivity
I can:
A
1
describe how the breakdown of an unstable nucleus results in radioactive emission and
the formation of a new element.
2
explain that a stable nucleus can become unstable by the absorption of neutrons.
3
explain that the level of background radiation, from a variety of sources, is higher in some
places than in others.
4
describe how to take background radioactivity into account when performing
experiments.
5
recall the relative penetration of alpha, beta and gamma emissions.
6
apply this knowledge to explain why different emissions are suited to particular purposes
to include sterilisation, thickness measurement, treatment of cancer, tracer techniques.
7
describe alpha, beta and gamma in terms of atomic particles and electromagnetic waves.
8
explain that the activity of a radioactive sample decreases with time.
9
attribute this decrease in activity to a corresponding decrease in the number of unstable
nuclei.
10
explain half-life as the average time for the number of undecayed nuclei in a sample to
halve.
11
explain that different radioactive materials decay at different rates.
12
use an activity–time graph to determine the half-life of a material.
13
describe how the half-life of a material can be measured.
14
apply an understanding of half-life to explain why different sources are suited to
particular purposes.
15
explain how measurements of the amounts of radioactive elements and their decay
products in rocks can be used to calculate the age of a rock.
16
interpret given information about developments in ideas of radioactivity from given
information.
17
recall that exposure to ionising radiation can be harmful.
18
describe the precautions that should be taken when handling radioactive materials.
19
describe some effects of radiation on the human body.
20
explain how the effects of radiation depend on the energy and penetration of the emission
as well as the amount of exposure.
B
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Physics TB6
Student checklist
I can:
1
A
recall the names and properties of bodies in the Universe:
the planets in the Solar System
comets
meteors
stars, galaxies and natural satellites.
2
explain that the orbit time of a planet depends on its distance from the Sun.
3
explain that the Moon remains in orbit around the Earth, and the planets orbit the Sun,
because of the gravitational attractive forces between them.
4
interpret given information about developments in ideas about models of the Solar
System.
5
explain that the orbit period of an artificial satellite increases with increasing height
above the Earth’s surface.
6
describe the variation in gravitational force with distance.
7
explain the variation in speed of a comet during its orbit around the Sun.
8
describe how stars evolve over a long timescale:
fusion, red giant, white dwarf, supernova, neutron star, black hole.
9
explain that theories for the origin of the Universe must take into account that
light from other galaxies is shifted to the red end of the spectrum
the further away galaxies are, the greater the red shift.
10
recognise that one way of explaining this is that
other galaxies are moving away from us very quickly
galaxies furthest from us are moving fastest.
11
explain how knowledge of the rate of expansion of the Universe enables its age to be
estimated.
12
explain that there are possible futures for the Universe depending on the amount of mass
in the Universe and the speed at which the galaxies are moving apart.
13
interpret given information about developments in ideas of the origin of the Universe.
14
discuss how scientists are trying to find evidence of life on other planets in the Solar
System and elsewhere in the Universe.
174
B
M
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Physics TB7
Student checklist
Using electricity
I can:
A
B
Electrostatic Phenomena
1
explain that when two objects rub together and become charged, electrons are transferred
from one object to the other.
2
explain how charging by contact and charging by induction occur in terms of the
movement of electrons.
3
recall that there are repulsive forces between objects with similar charges, and attractive
forces between objects with opposite charges.
Uses of Electrostatics
4
describe some everyday beneficial uses of electrostatic charge to include photocopying,
ink-jet printers and the removal of ash from the waste gases in a coal-burning power
station and where it should be avoided to include on the inner surface of a television
screen and when refuelling aircraft.
Electrostatics and Current
5
recall that current is a flow of charge.
6
state and be able to use the equation:
charge = current × time.
7
explain that the current in a metal is due to a flow of electrons from negative to positive.
explain that a current in an electrolytic solution is due to a flow of both positively and
negatively charged particles.
8
recall that the voltage between two points is the number of joules of energy transferred
for each coulomb of charge that passes between the points.
Electricity in the Home
9
state and be able to use the equation
power = voltage × current.
10
explain that a direct current is always in the same direction, but an alternating current
changes direction.
11
recall that energy is supplied to houses through the live wire and neutral wires.
12
recall that in normal use no current passes in the earth wire.
13
explain that the live wire has to be insulated from the earth and neutral wires.
14
explain how fuses and circuit breakers prevent fire due to electrical faults.
15
explain how the earth wire, together with the fuse or circuit breaker, prevents
electrocution.
16
explain why double-insulated appliances do not need an earth wire.
17
explain that energy can be transferred from the electricity supply as convection currents
and also as electromagnetic waves, including infra-red and microwaves.
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Physics TB7
Student checklist
I can:
18
A
use the equation:
energy = power × time
to calculate energy transfer in joules and kilowatt-hours.
19
recall that a domestic electricity meter measures the energy transfer in kilowatt-hours.
20
calculate the cost of electrical energy from a knowledge of the power, the time and the
unit cost.
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B
M
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Physics TB8
Student checklist
Electromagnetism
I can:
A
1
recall that a current-carrying conductor at right angles to a magnetic field experiences a
force.
2
describe the effect of reversing the current and the direction of the magnetic field.
3
explain how this effect is used in a simple electric motor.
4
describe the effect of changing the size of the current and the strength of the magnetic
field.
5
explain how the forces on a current-carrying coil in a magnetic field produce a turning
effect on the coil.
6
describe the use of a split-ring commutator in a simple d.c. motor.
7
recall that a voltage is induced in a conductor when it moves across a magnetic field.
8
recall that a voltage is induced in a conductor when the magnetic field through it
changes.
9
describe how the size of the induced voltage depends on the rate at which the change
occurs.
10
recall the effect of reversing the change.
11
explain that an alternating current is generated when a magnet rotates within a coil of
wire.
12
explain that a changing magnetic field in one coil of wire can induce a voltage in a
neighbouring coil.
13
explain that a transformer changes the size of an alternating voltage.
14
describe the construction of a transformer as two coils of wire wound on an iron core.
15
describe the difference in action and in construction of a step-up and a step-down
transformer.
16
Vp / Vs = Np / Ns.
17
B
Vp Ip = Vs Is.
18
describe the energy flow through a coal-burning power station.
19
discuss the social and environmental issues associated with different methods of
generating electricity.
20
explain that electricity is generated by rotating an electromagnet within coils of wire.
21
describe power losses in transmission.
22
explain why power is transmitted at high voltage.
23
describe the use of transformers in power transmission.
24
explain why the use of transformers dictates the use of alternating current.
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Student checklist
I can:
A
1
recall that the input signal for a logic gate is either a high voltage (about 5 V) or a low
voltage (about 0 V).
2
recall that the output of a logic gate is high or low depending on its input signals.
3
recall the truth tables of AND, OR, and NOT gates in terms of high and low signals.
4
recall how to use switches, LDRs and thermistors in series with resistors to provide input
signals for logic gates.
5
explain how an LED and series resistor can be used to indicate the output of a logic gate.
6
recall that a relay is needed for a logic gate to switch a current in a mains circuit because
a logic gate output cannot supply much power.
recall that a relay is needed for a logic gate to switch a current in a mains circuit because
the relay isolates the low voltage gate from the high-voltage mains.
7
recall that relays controlled by logic gates can be used to switch currents in circuits
containing heaters, motors, lights and locks.
8
explain how logic gates are used as part of an electronic system consisting of input,
processor and output device.
9
identify input, processor and output stages of an electronic system from a circuit diagram
employing logic gates.
10
recall how to work out the truth table of a logic system with up to three inputs made
from logic gates.
11
recall how to assemble a circuit of logic gates which obeys a given truth table of up to
eight rows.
12
recall the truth tables of NAND and NOR gates.
13
recall how to connect NOR and NAND gates to make a latch (bistable) circuit.
14
explain how, for a NOR and NAND gate latch, a brief high signal at one input results in a
permanent high signal at the latch output.
explain how, for a NOR and NAND gate latch, a brief high signal at the other input
causes a low signal at the latch output.
explain how, for a NOR and NAND gate latch, a low signal at both inputs leaves the latch
output signal unchanged
15
explain how two resistors can be used as a potential divider.
16
explain how one fixed resistor and one variable resistor in a potential divider allows
variation of the output voltage.
17
explain how to calculate the output signal of a potential divider from the values of its resistors.
18
explain how a thermistor and an LDR can be used with a fixed resistor to generate a
signal for a logic gate which depends on environmental conditions.
19
explain how a thermistor and an LDR can be used with a variable resistor to provide a
signal with an adjustable threshold for a logic gate.
178
B
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Physics TBA2
Student checklist
Processing waves
I can:
1
A
B
use the equation:
refractive index =
speed of light in vacuum
speed of light in medium
2
recall that dispersion occurs because waves of different wavelength travel at different
speeds in transparent materials.
3
explain dispersion in terms of refractive index.
4
describe the effect of a convex lens on a diverging beam of light.
describe the effect of a convex lens on a parallel beam of light.
5
recall that light incident on a convex lens parallel to the axis passes through the focal
point after passing through the lens.
6
recall how to find the position and size of the real image formed by a convex lens by
drawing rays from the object which pass through the centre of the lens.
recall how to find the position and size of the real image formed by a convex lens by
drawing rays from the object which moves parallel to the axis before the lens and pass
through the focal point after passing through the lens.
7
describe the use of a convex lens as a magnifying glass.
describe the use of a convex lens in a camera.
describe the use of a convex lens in a projector.
8
explain how a camera is focused.
explain how a projector is focused.
9
recall that all objects vibrate with a characteristic, or natural, frequency.
10
recall that the natural frequency of an object increases with decreasing mass.
11
recall that resonance occurs when an object is subjected to a vibration at its natural
frequency.
12
describe the effects of resonance in a pendulum.
describe the effects of resonance in a mass on a spring.
describe the effects of resonance in a vibrating string.
describe the effects of resonance in a column of air in a musical instrument.
13
recall that a musical instrument produces a sound when a column of air vibrates at its
natural frequency.
recall that a musical instrument produces a sound when a string vibrates at its natural
frequency.
14
recall that the natural frequency of a column of air decreases with increasing length of
the column.
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Physics TBA2
Student checklist
I can:
A
15
describe qualitatively how the natural frequency of a vibrating string depends on its
length, mass and tension.
16
recall that a string can vibrate in different modes, each with a different number of nodes.
17
recall that the frequency of a vibrating string increases with increasing number of nodes.
18
appreciate that the quality of the note from a stringed instrument depends on the relative
intensity of the modes of vibration.
19
use the displacement–time graph of a sound wave to determine its frequency.
use the displacement–time graph of a sound wave to determine its amplitude.
use the displacement–time graph of a sound wave to determine its quality.
20
recall that interference effects can be observed in sound waves.
recall that interference effects can be observed in surface water waves.
recall that interference effects can be observed in electromagnetic waves.
21
recall that interference of two waves results in a pattern of reinforcement and
cancellation of the waves.
22
describe a demonstration of interference using sound, water waves or microwaves.
23
explain interference effects in terms of constructive and destructive interference.
24
recall that the number of half-wavelengths in the path difference for two waves from the
same source is an odd number for destructive interference.
recall that the number of half-wavelengths in the path difference for two waves from the
same source is an even number for constructive interference.
25
180
interpret the developments in ideas about the nature of light from given information.
B
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Physics TBA3
Student checklist
I can:
A
1
recall that an acceleration preceded by a minus sign represents a deceleration.
2
calculate acceleration and displacement from a velocity–time graph.
3
B
recall the equations v = u + at , v2 = u2 + 2as and s = ut + 12 at2.
use these equations.
4
recall that an object projected horizontally in the Earth’s gravitational field, in the
absence of friction, has a constant horizontal velocity.
recall that an object projected horizontally in the Earth’s gravitational field, in the
absence of friction, has a steadily increasing vertical velocity.
5
describe the path of an object projected horizontally in the Earth’s gravitational field.
6
recall the equation: momentum = mass velocity.
use this equation.
7
recall that momentum is conserved.
8
apply the principle of momentum conservation to the interaction of two objects moving
in one dimension.
9
explain that there is a force on a rocket from its exhaust gases.
10
recall that rockets carry their own supply of fuel and oxygen.
11
recall that injuries in vehicle collisions are due to very rapid accelerations of parts of the
body.
12
explain that spreading acceleration over a longer time reduces the forces which act.
13
recall the use of crumple zones, air-bags and safety straps in cars.
14
recall the equation:
energy transfer = mass specific heat capacity temperature change.
use the equation.
appreciate some of the effects of materials having different specific heat capacities.
15
describe ways in which energy transfer from a house is reduced.
16
appreciate that in many processes energy is ultimately dissipated as heat in the
surroundings.
17
classify energy sources as renewable or non-renewable.
18
evaluate the advantages and disadvantages of geothermal, wind, fossil fuel, nuclear and
biomass as sources of energy.
19
describe how energy from renewable and non-renewable sources can be transferred to a
useful output.
20
evaluate the efficiencies of energy transfer devices by comparing energy input and useful
energy output.
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Physics TBA3
Student checklist
I can:
21
A
recall the equation:
efficiency =
use this equation.
182
useful work or energy output
.
total energy input
B
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Physics TB1
Answers in-text and Thinking further
Electric circuits
Introduction spread
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
(j)
A cells : lamps = 2:1 C cells : lamps = 1:2 (ratio = 1:1 in B).
A. Largest cell : lamps ratio so largest current. (Brightest lamp must
have greatest current.)
Ammeter. Amperes/amps/A.
Voltmeter. Volts/V.
Good conductors – e.g. copper, brass, iron etc. (metals)
Bad conductors – e.g. wood, paper, plastic etc.
One cell with two lamps in parallel.
Advantage: e.g. minimum amount of connecting wire needed/lamps
all in one long line so easier to arrange; voltage is shared so lots of low
voltage lamps can be used (e.g. 20 × 12 V lamps, 40 × 6 V etc.)
Disadvantage: e.g. one loose or broken lamp means none of them
work.
Two lamps, each with a switch, connected in parallel.
A1 = A2 = 2 A.
X. If both switches were closed the lamp would be short-circuited.
Spread 1.1
In-text questions
(a)
(b)
Sound energy (+ some thermal energy).
P off, Q off; R on, S off.
Thinking further questions
■1 Place a resistor in series with the LED.
■2 The resistor becomes hotter.
There are more and/or faster electrons to collide with the resistor’s atoms
so more KE is transferred. Atoms of resistor vibrate more, so resistor
becomes hotter.
◆3 Two LED’s in parallel but facing in opposite directions, in series with the
power supply.
Two LED’s ensures that the circuit is working as one LED is always lit.
◆4 High melting point, good electrical conductor, ductile.
Spread 1.2
In-text questions
(a)
(b)
(c)
(d)
P = 2 A Q = 1 A R = 3 A.
V1 = 4 V V2 = 8 V.
0 V.
V = IR = 3 × 8 = 24 V.
■1 12 V 6 Ω 0.25 A.
■2 (a) 0.5 A current through battery = 1.5 A.
(b) VA = VB = 6 V VC = 12 V.
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◆3 12 V battery with starter motor, lights and wipers connected in parallel,
each with a switch. Starter motor needs a large current so the lamps have
less current, hence they are dimmer.
◆4 (a) Supply with two lamps in parallel; the dimmer one has a resistor in
series with it.
(b) As in (a) but the resistor is replaced by a variable resistor.
Spread 1.3
In-text questions
(a)
(b)
(c)
(d)
(e)
Keep current/supply voltage low; switch on only to take readings.
Filament gets very hot so resistance does not remain constant/
resistance increases.
Current values read from graph.
At 2 V
I = 0.26 A
R = 2/0.26 = 7.7 ohms
At 4 V
I = 0.34 A
R = 4/0.34 = 11.8 ohms
At 6 V
I = 0.40 A
R = 6/0.40 = 15.0 ohms
Resistance increases as voltage increases.
Thermistor – more electrons released so current increases and
resistance decreases. Metal wire – greater lattice vibrations so
resistance increases and current decreases.
More free electrons per unit length so current greater and resistance
smaller.
■1 Curved graph as in fig 16.
Similar shaped curve, from (0, 0), but above original curve.
■2 At low voltage there is a very high resistance, then the resistance decreases
suddenly and becomes very small, leading to a rapid rise in current.
When voltage is reversed there is no current so the resistance becomes
extremely large.
■3 Resistance of LDR increases in the dark so the current decreases. Hence
the milliammeter reading will decrease.
◆4 (a) When first switched on the filament is cold so has a low resistance
and therefore the current is high (I = V/R).
(b) The cold thermistor has a high resistance so keeps the current low at
first. As the filament and the thermistor heat up, the filament
resistance increases and the thermistor resistance decreases.
◆5 Power supply, resistor and LED (with arrow on symbol pointing in the
same direction as the current), all in series.
Voltage across resistor = 10 V. R = V/I = 10/0.020 = 500 ohms.
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Answers: end of teaching block
Electric circuits
Answers
●1 thermal, light, amperes, ammeter, series, voltage, voltmeter, parallel, voltage, current, ohms. 11
6V
●2 Circuit.
Voltmeter reading = 3 V.
3
4
●(a) Axes scaled; axes labelled – quantity and unit; plots;
straight line.
OR
for lamps
4
●(b) Resistance is constant; resistance = 10 ohms (approx.) from gradient of graph or by
averaging values calculated from table.
2
■(c) (i)
2
0.19–0.21 A
(ii) 6.2–6.3 V.
●(a) X – ammeter; 2 A.
2
●(b) Y – voltmeter; 8 V.
2
■(c) M = V/I = 4/2 = 2 ohms; N = 8/2 = 4 ohms.
4
■5
6
V
3
1
(i) S open – both equally bright/normal brightness; same current in each lamp.
(ii) S closed – A out; B brighter than before; S closed gives lower resistance path for
current/short circuit/lamp shorted; less resistance so bigger current in circuit
(so B brighter).
6
■(a) R = V/I = 2.5/3 = 8.3 ohms.
◆(b) (i)
3
supply, lamp, variable resistor, ammeter in series, voltmeter in parallel across lamp. 3
(ii) I–V graph as Figure 16.
7
8
9
10
As current increases there are more free electrons to collide with the atoms/ions in the
filament; more KE transferred/vibrations increase; the temperature/resistance of the
filament increases.
5
◆(c) 6 V power supply, lamp and resistor in series
R = (6 – 2.5)/0.3 = 3.5/0.3 = 11.7 ohms.
5
■(a) Fog lamp is in series with the headlamps; so voltage is shared; and current is less
than normal.
3
■(b) Fog lamp now short-circuited.
1
◆(c) Circuit – fog lamp and switch in parallel with car battery.
3
■(a) Ammeter reading increases; resistance of LDR is low in the light; so current
(I = V/R) increases.
3
◆(b) Current too small/resistance in circuit too large; increase voltage of power supply.
2
■(a) 170 ± 10 ohms.
1
■(b) Temperature when R = 100 ohms = 55°C; temperature when R = 250 ohms = 12°C;
temperature change = 55 – 12 = 43°C.
3
◆(c) Low temperatures; graph steepest here.
2
◆(d) Controlling temperature of any process up to (say) 20°C.
1
(a)
If a metal is cooled, its atoms vibrate less; offering less obstruction to the electrons.
2
(b)
No resistance to current; so no energy wasted as heat.
2
(c)
Temperature below which a material becomes superconducting.
1
(d)
It only occurred at extremely low temperatures; materials with higher critical
temperatures are now available.
2
(e)
Magnetic resonance imaging.
1
(f)
Virtually no friction; so it could go faster/use less fuel.
2
(g)
No expensive/bulky cooling equipment needed; process would be very efficient as no
energy would be wasted as heat.
2
Long cables could transfer energy without loss/power transmission lines/thinner
wires could be used/avoid use of expensive cooling systems.
1
(h)
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Physics TB2
Forces and energy
Introduction spread
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
(j)
Change the shape/size/speed/direction of motion of an object. (Any 3)
Newton (N).
Average speed = 800 m/40 s = 20 m/s.
10 N.
20 N.
Friction force is less so car’s tyres do not grip the road as well.
2 m from pivot on RHS/1 m from right hand end.
gravitational potential energy; changes to kinetic energy.
Temperature is the degree of hotness of an object; heat is the quantity
of thermal energy it possesses so depends on the mass and material of
the object as well as its temperature.
conduction, convection, radiation, evaporation.
Spread 2.1
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
Moment of force = 200 N × 0.15 m = 30 Nm.
Moment of Priya = 400 N × 2 m = 800 Nm.
Moment of Dan = 500 N × 2 m = 1000 Nm.
Anticlockwise.
Dan could move closer to the pivot
Priya could hold something weighing 100 N
They could move the pivot towards Dan
Another person could sit on Priya’s side.
F × 1 m = 800 N × 0.4 m F = 320 N.
Diagrams showing pivot and applied force each time. Explanation to
include the principle of moments so that a small force a large distance
from the pivot can lift a large force close to the pivot.
■1 Long spanner. The force is applied at a greater distance from the nut (pivot) so the force is less to
provide the same moment.
■2 (a) No effect as his moment about the pivot is zero.
(b) Seesaw will go down on the LHS.
◆3 (a) Taking moments about B: FA × 80 m = 120 kN × 50 m FA = 75 kN.
(b) Force at B = 120 – 75 = 45 kN
Assumed that the weight of the bridge is negligible compared with the
weight of the lorry so can be ignored.
(c) Graph of FA against distance from A – straight line changing from F =
120 kN at A to 0 kN at B.
◆4 Pivot the metre rule at its centre of mass. Put the 1 N weight at one end.
Place the block on the other side of the pivot and adjust its position until
the rule balances. Note its distance from the pivot. Use the principle of
moments to calculate a value for the weight of the block.
(a) Use a larger weight than 1 N; for example, a 10 or 12 N weight.
(b) A tiny movement of the weights makes the rule unbalanced.
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Spread 2.2
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
It is an average speed because it is impossible to keep the speed
constant all the time.
Average speed = 2000 m/356.24 s = 5.614 m/s.
Speed = 20/8 = 2.5 m/s
Gradient is increasing in (b) and decreasing in (c).
Speed after 4 s = gradient of tangent at t = 4 s = (approx.) 23/6.6 =
3.5 m/s
4.2 m/s
3.1 m/s
Speed decreases as time increases.
In fig 20 distance travelled = ½ × 6 × 10 = 30 m.
In fig 21 distance travelled = 30 m.
■1 Average speed = 12/0.33 = 36 km/h
Time = 12/48 = 0.25 hours or 15 minutes.
■2 Graph.
(a) Uniform speed of 20 m/s for 5 s, stopped for 3 s, uniform speed of
30 m/s for 2 s.
(b) Average speed = 160/10 = 16 m/s.
◆3 (a) Graph.
(b) Average speed = 130/2.5 = 52 km/h.
(c) Line on graph starting at t = 9.00 am when distance from Luton = 130
km and reaching 0 km at 10.30 am with no horizontal sections.
Two cars pass where graphs cross. Estimate because table only gives
the distance from Luton every 30 minutes. (Car could have stopped or
speed changed during each 30 minute interval.) Answer for second car
will depend on how the graph is drawn.
Spread 2.3
In-text questions
(a)
(b)
(c)
OA constant velocity of 3.3 m/s
AB constant velocity of 5 m/s in opposite direction, back to starting
point
BC constant velocity of 5 m/s on opposite side of starting point
CD constant velocity of 2.5 m/s in opposite direction, back to
starting point.
Graph with increasing and decreasing gradients.
90 km/h = 90/3.6 = 25 m/s.
■1 (a) 0 (b) 50 m/s (c) 0.
■2 (a) 36.1 m/s (b) 1188 km/h.
◆3 Graph
(a) distance travelled = sum of areas above and below the time axis
= 32 km.
(b) displacement = 0 since areas above and below the time axis are equal.
◆4 (a) 1885 s.
(b) 0.40 m/s.
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Spread 2.4
In-text questions
2
acceleration = (12 – 8)/4 = 1 m/s .
2
OA constant acceleration of 5 m/s from rest
2
AB constant deceleration of 5 m/s to stop at B
2
BC constant acceleration of 2.5 m/s in opposite direction
2
CD constant deceleration of 2.5 m/s to stop at D
Object does not return to its starting point because the areas OAB and
BCD are not equal.
(a)
(b)
■1 Speed is constant but direction is changing; therefore cyclist is
accelerating.
2
■2 130 km/h = 36(.1) m/s, acceleration = 36/12 = 3 m/s .
◆3 velocity – time graph.
2
(a) Acceleration = 20/16 = 1.25 m/s .
2
(b) Retardation = 20/40 = 0.5 m/s .
(c) Distance travelled = ½ (60 + 116) × 20 = 1760 m.
2
◆4 Constant retardation of 5/0.5 = 10 m/s followed by constant acceleration
2
of 10 m/s in the opposite direction. It returns to its starting point as the
total displacement (area under graph) is zero.
The graph could represent a ball thrown vertically upwards at 5 m/s.
Spread 2.5
In-text questions
(a)
(b)
(c)
Jo will move backwards.
The planets are attracted to the Sun (gravitational attraction). The Sun
is much more massive than the planets so they orbit the Sun at such a
distance and velocity that they are in equilibrium.
mass
(i) weight on Earth
(ii) weight on Moon
45 kg
450 N
75 N
100 g
1N
0.16 N
1 kg
10 N
1.6 N
■1 (a) by lubrication/oiling.
(b) E.g. walking/car wheels turning/car brakes.
■2 (a) 720 N.
(b) 1440 N.
(c) 72 kg.
◆3 The chair is pushing up on Amy with a force of 450 N.
◆4 Electrostatic force of attraction between the positively charged nucleus
and the negatively charged electrons. Electron mass is much smaller than
the mass of the nucleus so the electrons orbit the nucleus (in the same way
as the planets orbit the Sun).
Spread 2.6
In-text questions
(a)
(b)
(c)
188
Accelerates (i) to right (ii) up (iii) to left and down
and up.
To reduce air resistance enabling them to go faster.
To reduce air resistance enabling them to go faster.
(iv) to right
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Physics TB2
■1 Diagram showing A weight down, B lift up, C thrust forwards, D drag
backwards.
Length of arrows for A = B and C = D.
(a) accelerates (b) decelerates (c) lift force must increase.
■2 200 N Box slows down.
■3 Constant velocity.
6
◆4 (a) 7 × 10 N.
(b) The resultant force will increase due to (a) mass decreasing as fuel is
used up, (b) g decreasing as height increases.
(c) Its acceleration increases.
◆5 (a) Speed is constant so there is no resultant force; therefore the tension
in the tow-bar equals the forward thrust.
(b) 400 N
(c) Tension in tow rope = 400 N
resistance to motion = 400 N
weight = 10 000 N
normal reaction force = 10 000 N.
Spread 2.7
In-text questions
(a)
(b)
(c)
(d)
(e)
As the mass (and hence weight) of the trolley changes, the force down
the ramp will change. The angle of the slope must be changed so that
the force down the slope is equal to the friction force once more.
a against 1/m. Graph would be a straight line through the origin.
60 N.
The force is in the opposite direction to the direction of motion.
For a given force and mass F = ma fixes the acceleration.
Acceleration = change in velocity/time so the longer the time the
greater the velocity change produced.
◆1
◆2
◆3
◆4
2
5 m/s .
2
3 m/s .
To give the maximum acceleration.
2
2.5 m/s .
Spread 2.8
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
1500 J.
1500 J.
Paul’s power = 1500/20 = 75 W; Pat’s power = 1500/60 = 25 W.
GPE = 9 J.
WD = 9 J (same as answer to (d)).
KE gained = GPE lost = 9 J.
6 m/s.
GPE = 4.5 J KE = 4.5 J.
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Physics TB2
■1
■2
■3
◆4
◆5
90 000 J.
(a) weight = 500 N (b) WD = 150 000 J (c) Power = 167 W.
(a) 720 N (b) 120 N (c) 0 N.
Darren’s KE = 4320 J; Meera’s KE = 2160 J – this is half of Darren’s KE.
(a) GPE = 3500 J (b) 10 m/s.
Spread 2.9
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(i) 7 m (ii) 21 m (iii) Graph – straight line through the origin of
gradient 0.7.
Braking distance increases with mass and speed as the vehicle has
more energy to lose in stopping. (H level students may see that it is
2
2
proportional to mass and to (speed) by reference to KE = 1/2 mv but
this comes later in the text.)
Good brakes and good grip reduce the braking distance as both
increase the friction force.
5000 N.
54 m.
Thinking distance = 14 m as before but braking distance = 80 m
(doubles). Stopping distance becomes 94 m.
Larger mass means larger braking distance (they are proportional) so
stopping distance increases. If speed increases too, the braking
2
distance is proportional to (speed) so increases even more rapidly.
More KE to lose means more damage done in the event of an accident.
■1
speed
thinking
braking
stopping
(m/s)
distance (m) distance (m) distance (m)
15
9
20
29
20
12
35
47
25
15
55
70
30
18
80
98
Thinking distance goes up by 3 each time but the braking distance and
stopping distance increase much more rapidly. When speed doubles the
braking distance quadruples.
■2 Thinking distance = 40 m compared with a ‘normal’ value of 12 m.
Stopping distance will be much greater. Reference to values in table in Q1.
◆3 Smooth tread has less friction so the braking distance will increase. Tread
also prevents aquaplaning in wet weather; this also reduces friction with
the road and increases the braking distance.
◆4 KE = 112 500 J. Braking force = 112 500/20 = 5625 N.
Spread 2.10
In-text questions
(a)
(b)
(c)
190
A ping-pong ball weighs less so the air resistance force will equal the
weight at a lower speed than for a golf ball. This means that terminal
velocity is reached at a lower height for the ping-pong ball.
As the resistive force is greater, it will equal the weight at a lower
speed and so more quickly. The terminal velocity is therefore less.
600 N.
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Physics TB2
(d)
(e)
Upright position means the air resistance force is less so she will be
moving faster before the forces on her become balanced. Therefore her
terminal velocity will be greater.
2
Speed – time graph. Acceleration of 10 m/s at first, decreasing
gradually until terminal velocity is reached. When parachute opens
there is a rapid deceleration to a new, much lower, terminal velocity
until the parachutist is brought to rest on hitting the ground.
■1 Use light gates to measure the velocity of the marble at 10 cm intervals as
it falls/the time taken to fall successive 10 cm intervals. If it reaches
terminal velocity the velocity/time will become constant.
■2 Graph. Linear up to d = 80 cm (approx.) then air resistance force becomes
significant so acceleration decreases and the rate of increase of b also
decreases.
s
◆3 weight = mg F = ma becomes mg = ma therefore a = g = 10 m/s near the
Earth’s surface.
◆4 m = 0.1 kg is falling at a constant speed (a = 0) as the air resistance force
equals its weight.
2
m = 1 kg has an acceleration of 9 m/s . Its speed is increasing but the value
of its acceleration will gradually decrease as the air resistance force
continues to increase.
Spread 2.11
In-text questions
(a)
(b)
(c)
(d)
(e)
Hardly any free electrons.
Hot water rises.
The atoms have fixed lattice positions so cannot move around.
Heat is transferred through the metal wall of the radiator by
conduction; this heats the air adjacent to the radiator, setting up a
convection current which gradually heats the whole room. There is a
little radiation from the hot metal wall of the radiator but the main
method of heat transfer is convection.
insulation
cost
annual saving
pay-back time
cavity wall insulation
£600
£30
20 years
double glazing
£3000
£60
50 years
draught-proofing
£40
£20
2 years
loft insulation
£400
£80
5 years
jacket for hot water tank
£15
£15
1 year
jacket for hot water tank.
■1 Colder, denser air sinks and warmer air rises, to be cooled by the freezer
compartment, so cooling the whole of the fridge by convection.
■2 To provide a fresh supply of oxygen, avoiding risk of suffocation.
■3 Terraced house has fewer outside walls so energy loss through the walls
is less.
◆4 loft insulation – conduction
carpets and curtains – conduction
double glazing – conduction
cavity wall insulation – conduction and convention
draught proofing – convection
lagging of hot water tank – conduction and radiation.
191
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Physics TB2
◆5 Thermostats to control the temperature of each room/turn down the
thermostat temperature/do not heat all the rooms/have the heating on for
less time each day/wear warmer clothing.
Spread 2.12
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
lubrication.
8%.
(i) 15 W (ii) 60%.
40%.
walls – 2000 W floor – 600 W
6600 W.
ordinary – 35% CHP – 80%.
windows – 1500 W.
■1
■2
◆3
◆4
10 000 MW
(a) 30% (b) transferred to heat and some sound
26.7%
Cavity wall insulation/double glazing/small windows/thick carpets and
curtains/hot water tank and pipes well insulated/loft insulation/draught
proofing/solar panels in roof/grass roof.
192
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Physics TB2
Forces and energy
Answers
●1 mass, kilograms, weight, gravity, newtons, mass, weight, energy, joules, gravitational
potential, kinetic, efficient, heat, sound.
14
■2 clockwise = anticlockwise moments; 1x = 0.9 × 0.2; x = 0.18 m (18 cm) from pivot – from
12 cm mark on rule.
5
Diagram.
●3 (a)
4
5
6
A = lift; B = thrust; C = weight; D = drag.
4
(b)
A = C; B = D.
2
(c)
A, B and D increase. C is unchanged (ignoring change in g).
4
●(a) E.g. Walking/car wheels turning/car brakes.
2
■(b) Energy is transferred to heat energy.
2
●(a) GPE, KE.
2
●(b) GPE increases, KE stays the same.
2
■(c) 1000 N.
1
●(a) (i) GPE max. at A
(ii) KE max. at B.
2
■(b) decelerating, KE is being converted to GPE.
■7 (a)
(b)
2
velocity–time graph.
(i)
4
2
acceleration = velocity change/time = (15 – 0)/15 = 1 m/s .
3
2
(c)
8
12
(iii) distance = area under graph = (1/2 × 15 × 15) + (25 × 15) + (1/2 × 15 × 20) = 637.5 m;
4
resultant force is zero so forces are balanced.
1
2
◆(b) (i)
2
(b)
11
2
■(a) energy efficiency = useful energy output/total energy input.
◆9 (a)
10
(ii) deceleration = (0 – 15)/20 = (–) 0.75 m/s .
energy that would be wasted is used to provide useful heating.
(ii) power station must be near the buildings to be heated/slightly less electricity
is produced.
1
Molly will be thrown forwards (possibly through the windscreen) because the brakes
act on the car, not on Molly so she carries on moving forward at her original speed;
3
Molly would not be thrown forwards. The seat belt would have stretched slightly
and slowed Molly down gradually; so that there would be less force on her.
2
●(a) At B, GPE + KE, at C elastic PE (+ some thermal energy), at D, GPE.
4
■(b) (i)
5
GPE = mgh; GPE at A = 0.05 × 10 × 1.0 = 0.5 J, GPE at D = 0.05 × 10 × 0.2 = 0.1 J
(ii) energy ‘lost’ = 0.5 – 0.1 = 0.4 J.
2
(iii) transferred to thermal energy (and sound) on impact; transferred to thermal
energy due to air resistance.
2
■(a) (i) 1 N (ii) 3 N.
2
◆(b) same.
1
◆(c) Air resistance is a greater proportion of the weight of A than of B so the acceleration
of A is reduced more than that of B, so A travels more slowly (and takes longer to
reach the bottom).
3
●(a) constant velocity.
1
■(b) WD = force × distance moved = 500 × 25 = 12500 J.
3
■(c) 12500 W.
1
■(d) efficiency = useful power output/total power input = 12 500/50 000 = 0.25 (25%).
3
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Physics TB2
■(e) bigger force forwards than backwards/resultant force forwards.
1
◆(f) as speed increases, air resistance increases as well; eventually the air resistance force
is equal to 700 N so the acceleration is zero (balanced forces).
2
■13 (a)
14
15
400 N.
1
(b)
WD = force × distance moved = 400 × 15 = 6000 J.
3
(c)
6000 J.
1
(d)
efficiency = useful power output/total power input = 6000/10 000 = 0.6 (60%).
3
(e)
time.
1
●(a) Air trapped in cavity is a bad conductor of heat so heat transfer from inside to outside
is greatly reduced.
3
■(b) Mineral wool prevents large convection currents circulating in the cavity, this led to
heat loss by convection in the 1950 house.
2
■(c) Better sound insulation/cheaper fuel bills.
2
■(a) Average speed = total distance/total time = 650/5 = 130 km/h(i) = 130/3.6 = 36.1 m/s (ii).
This is an average speed because the train will accelerate/decelerate/stop on the way.
6
◆(b) F = MA, F = 300 000 × 0.5 = 150 000 N .
3
2
16
◆(c) a = F/m = 150 000/250 000 = 0.6 m/s .
3
◆(d) Distance left = 400 km; time = 2 hours 48 min = 2.8 hours;
average speed = 400/2.8 = 143 km/h.
4
■(a) Thinking distance = speed × time = 220 × 0.7 = 14 m.
3
■(b) Graph – constant speed of 20 m/s for 0.7 s then steady deceleration to stop after a
further 4 s.
4
2
◆(c) Deceleration = velocity change/time = 20/4 = 5 m/s .
3
◆(d) Distance travelled = area under graph = (20 × 0.7) + (1/2 × 20 × 4) = 54 m; so yes.
4
◆(e) at 25 m/s the braking time would be 5 s. Stopping distance would be
(25 × 0.7) + (1/2 × 25 × 5) = 80 m (so would hit child).
4
◆17 (a)
(i)
2
Acceleration = F/m = (90 000 – 30 000)/3000 = 20 m/s .
4
(ii) Velocity after 3 s = acceleration × time = 20 × 3 = 60 m/s.
(b)
18
2
3
2
Acceleration = –10 m/s (or deceleration of 10 m/s ).
1
■(a) Thinking time = distance/speed = 6/10 or 9/15 = 0.6 s.
■(b)
speed
m/s
10
15
20
25
30
35
thinking
distance
in m
6
9
12
15
18
21
braking
distance
in m
6
14
24
38
55
74
stopping
distance
in m
12
23
36
53
73
95
3
KE (answer to g (i))
in J
30 000
67 500
120 000
187 500
270 000
367 500
5
■(c) Increases proportionally.
2
■(d) Increase, the driver’s brain would take longer to react.
2
■(e) Increase, friction force reduced.
2
◆(f) Assuming both sets of brakes are equally efficient, the minimum distance apart
should be the thinking distance of 18 m so allowing for variations in reaction
times and brakes a little more than 18 m should be allowed.
3
◆(g) (i)
6
See table above.
(ii) Graph.
194
4
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Physics TB2
(iii) KE and braking distance are proportional since graph is a straight line through
the origin.
(2)
(iv) Braking force × distance = change in KE, so gradient of graph = braking force.
Calculation of gradient – large triangle, read accurately, correct calculation.
Braking force in N (approximately 5000 N).
19
(a)
(b)
(c)
(6)
Terminal velocity is the constant velocity reached by a falling object when its weight
is equal to the upward resistive force.
(2)
With arms outstretched the person displaces more air molecules so the air resistance
force is greater and (s)he reaches terminal velocity sooner so at a lower velocity.
(3)
(i)
(1)
density is very low.
(ii) Fewer molecules per unit volume means the air resistance force is smaller so it
takes longer to reach terminal velocity and its value is higher.
(2)
(d)
Friction with the air molecules when falling at a high speed produces lots of heat.
(2)
(e)
High melting point/good thermal insulator/flexible, soft.
(2)
(f)
The air is very thin/density low/fewer molecules per unit volume at such a high
altitude so the air pressure is so low that, even allowing for the increase on reaching
the speed of sound, it will not become too large.
(2)
As the air thickens (its density increases) the air resistance force will increase; so
that it becomes greater than his weight; this will make him decelerate.
(3)
Parachute opens – greater upward force so rapid deceleration; reaches a new, lower
terminal velocity; gradually comes to rest on hitting the ground (bends knees so he
stops more slowly).
(3)
(g)
(h)
195
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Physics TB3
Wave properties
Introduction spread
In-text questions
(a)
Vibrates it.
(b)
Damage hearing/go deaf.
(c)
Stars are luminous/produce their own light, moon reflects light from Sun.
(d)
Rays drawn with ruler, passing through pinhole, inverted image.
(e)
Straight lines from footballer through periscope to eye, good reflections on mirror.
Spread 3.1
In-text questions
(a)
strings.
(b)
skin.
(c)
reed.
(d)
transverse.
■1 Water moves up and down,
wave moves outwards,
boat only moves up and down.
■2 Moving weight up causes compression, takes time to move up reflect and return.
Spread 3.2
In-text questions
(a)
30 ÷ 60, = 0.5 Hz.
(b)
metre.
(c)
5 mm, 16 mm
(d)
16 mm
(e)
speed = distance ÷ time = 100 ÷ 20 = 5 m/s.
■1 (a)
(b)
increases/higher.
decreases, to half.
■2 speed = frequency × wavelength = 7 × 0.2 (or 7 × 20) = 1.4 m/s (or 140 cm/s).
◆3 (a)
(b)
distance = speed × time = 300 × 0.75 = 225 m.
speed of light very much larger/infinite.
Spread 3.3
In-text questions
(a)
Angle of incidence equals angle of reflection.
(b)
Originate from or converge to a point which is closer to barrier than centre of circle
which forms the barrier, or words to that effect.
196
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Physics TB3
■1 (a)
(b)
30°
Wavefronts drawn with ruler, incident with wavelength of 2 cm, reflected with same
wavelength as incident, angle of incidence at 30°, angle of reflection same as angle of
incidence
◆2 6 wavefronts shown, 4 incident, 2 reflected, 8 cm accurate, 2 cm accurate, reflected
originate 8 cm behind barrier.
Spread 3.4
In-text-questions
(a)
65°.
(b)
at focus.
(c)
rays drawn with ruler, reflected rays appear to diverge from focus.
■1 Wider field of view, or words to that effect.
■2 Soft material, absorb sound/reduce reverberation.
◆3 (a)
(b)
gets even wider.
difficult to mark exact position of centre of ray.
Spread 3.5
In-text questions
(a)
speed = frequency × wavelength, if speed is lower then wavelength decreases if
frequency stays same.
(b)
equal.
■1 Waves drawn with ruler, consistent wavelength, refraction at deeper water, longer
wavelength in deeper water, consistent wavelength, angle of refraction greater than
angle of incidence.
◆2 (a)
(b)
Points correctly plotted, smooth curve drawn, comments on curve, decreasing gradient/
levels off, passing through origin.
Sines correct to 2DP
0.17; 0.34; 0.50; 0.64; 0.77; 0.87; 0.94
0.12; 0.22; 0.33; 0.42; 0.52; 0.57; 0.63.
Straight line drawn with ruler, comments on straight line, passing through origin/
proportional.
Spread 3.6
In-text questions
(a)
On the film.
(b)
Appears to raise left hand.
(c)
To make sure the reading is taken at correct angle/line up image of needle behind needle.
(d)
(360 ÷ angle between mirrors) – 1
(e)
Infinite number, angle between mirrors is zero.
197
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Physics TB3
■1 Driver of car in front sees writing correct way round in rear view mirror or words to that
effect.
■2 Below where he sees the fish.
◆3 Raises right hand.
Spread 3.7
In-text questions
(a)
0.5 m.
(b)
1 m.
(c)
Radio 4 – 1500 m
Radio 5 – 330 m
–6
m/0.000 003 m/3 ␮m
(d)
3 × 10
(e)
Door width comparable to wavelength of sound, much bigger than wavelength of
light, light does not diffract.
■1 (a)
(b)
◆2 (a)
(b)
198
Idea that long waves diffract most and short waves and microwaves diffract least,
idea that no/little diffraction needed to receive at house D, idea that a lot of diffraction
needed to receive at house A.
Taller/higher aerial.
1 cm diameter light spot, sharp edges.
Light spot larger than pinhole diameter.
M
?
Physics TB3
Wave properties
Answers
●1 (a)
true
(b)
false
(c)
true
(d)
false
(e)
true.
5
Air vibrates, longitudinal wave/compressions and rarefactions.
2
Vibrates, at 600 Hz.
2
●2 (a)
(b)
●3 X – C, Y – A, Z – B.
3
●4 D.
1
●5 D.
1
■6 450 m/s, 5 m/s, 4 m, 40 Hz, 1.67 Hz.
5
■7 1.7 m tall, 3 m, behind mirror/virtual, on same normal, walking southerly, upright,
waves left hand.
7
■8 distance = speed × time, = 330 × 5, = 1650 m.
3
■9 (a)
(b)
10
Mirrors on both cushions, shine light from above white ball to RH mirror, adjust
angle, until reflection from bottom mirror hits red.
4
Balls behave like light, angle of incidence equals angle of reflection.
2
■(a) Points plotted correctly, smooth curve.
2
■(b) 72°.
1
■(c) 8.
1
◆(d) 4.
1
◆(e) Graph gives value of 3.5 images, cannot have part of an image.
2
■11 Curved shape with wave having travelled further towards AB.
1
■12 (a)
increases.
1
(b)
unchanged.
1
(c)
increases.
1
13
■(a) Wavefronts continue to be straight showing no diffraction, consistent wavelength
before harbour entrance, same wavelength inside harbour.
3
◆(b) Wavefronts semicircular showing diffraction inside harbour, consistent wavelength.
2
◆(c) Wavelength from large yacht similar to harbour entrance gap, very short wavelength
from motorboat much less than harbour entrance gap, diffraction only if similar
distances.
3
199
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Physics TB4
Using waves
Introduction spread
In-text questions
(a)
red, orange, yellow, green, blue, indigo, violet
right order.
(b)
red and blue ➞ magenta
blue and green ➞ cyan
green and red ➞ yellow
red and blue and green ➞ white.
red tomato + red light ➞ red
blue car + green light ➞ black
yellow daffodil + red light ➞ red
white paper + yellow light ➞ yellow.
(c)
Spread 4.1
In-text questions
(a)
frequency = velocity/wavelength = 300 000 000/1500 = 200 000 Hz (200 kHz).
(b)
wavelength = velocity/frequency = 300 000 000/10
(c)
violet.
18
= 3 × 10
–10
m.
■1 Gamma rays have shorter wavelength than X-rays, X-rays have shorter wavelength
than visible light, the shorter the wavelength the more energetic, the more energetic
the more penetrating.
19
23
◆2 gamma
10 Hz – 10 Hz
17
19
X-rays
10 Hz – 10 Hz
15
17
ultraviolet
10 Hz – 10 Hz
11
15
infrared
10 Hz – 10 Hz
3
12
radio
10 Hz – 10 Hz.
(answers to within an order of magnitude).
Spread 4.2
In-text questions
(a)
Blue flames emit light with a shorter wavelength, shorter wavelengths have more
energy.
(b)
Foil reflects radiation back to the potato.
(c)
20 × 15, = 300 minutes (5 hours).
■1 Reduce amount of ultraviolet radiation to the eyes.
■2 Working underground/little sunlight, therefore little exposure to ultraviolet radiation,
ultraviolet radiation helps in the production of vitamin D.
◆3 Car engine hot, tyres hot, people in car.
200
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Physics TB4
Spread 4.3
In-text questions
(a)
Microwaves can penetrate flesh, transfer energy to water in human body.
(b)
Very short wavelength, almost no diffraction.
(c)
Short wavelength, little diffraction.
(d)
uhf has to be almost in line of sight since little diffraction/uhf is ground based
transmission and reception, satellite dishes have to be in line of sight/satellite
is in line of sight since no obstructions such as hills or tall buildings.
(e)
Frequent exposure to X-radiation is damaging to the human body.
(f)
Lead vest, absorb X-rays, reduce exposure/damage to patient.
(g)
100 000 000 m/s.
■1 time = distance/speed = 90 000/300 000 = 0.3 s.
■2 long waves are reflected from the ionosphere, greater diffraction.
◆3 (a)
8
distance = speed × time = 3 × 10 × 6 × 10
–7
= 180 m.
(b)
90 m.
(c)
No need to adjust, distance between cars greater than stopping distance.
◆4 X-rays or gamma rays have wavelengths of similar order of size to atomic distances,
therefore diffraction takes place.
Spread 4.4
In-text questions
(a)
Different colours have different wavelengths, therefore refract at different angles.
(b)
Entering along the normal/right angle to surface.
(c)
45°, greater than critical angle.
(d)
Current produces heating effect, energy lost, very little light loss in optical fibre,
little energy lost.
■1 No interference in signal.
◆2 Does not matter how the light passes, important to see image in the same pattern
as the object.
Spread 4.5
In-text questions
(a)
Stronger reflected signal, received sooner.
(b)
Distance = speed × time = 1500 × 0.4 = 600 there and back, depth = 300 m.
(c)
Looking for fish/submarines.
(d)
To collect low sound levels.
(e)
Emits signal, reflected off opposite wall, time taken for reflection halved,
distance = speed × time.
■1 (a)
wavelength = velocity/frequency = 1500/150 000, 0.01 m
201
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Physics TB4
(b)
boat slower than dolphin.
(c)
distance = speed × time = 1500 × 0.05 = 75 there and back, fish distance = 37.5 m.
◆2 Audible frequency means relatively long wavelength, sound diffracts around fish,
ultrasound is reflected.
Spread 4.6
In-text questions
(a)
Produced by vibration, P waves are longitudinal, travel through dense objects.
◆1 Most densely populated cities are in earthquake zones.
◆2 (a)
(b)
seismometer S left to right P wave, S wave, L wave.
T is in shadow of core, no S wave detected.
Spread 4.7
In-text questions
(a)
S waves do not travel through liquids so shadow confirms outer liquid core,
reverberations indicate that not all core is liquid therefore a solid inner core.
(b)
Rock type.
(c)
Less dense than surroundings.
(d)
Crust.
(e)
12/12 800 = 0.000 9375 (0.093 75%).
■1 (a)
(b)
Similar coastal outlines, fossil evidence from cynognathus, mesosaurus, glossopteris.
Fossil evidence from lystrosaurus, glossopteris.
3
◆2 Average density of core and mantle greater than 5.5 g/cm .
Spread 4.8
In-text questions
(a)
Plate boundaries correspond to major earthquake zones.
■1 (a)
(b)
Friction.
Forms part of the mantle.
◆2 speed = distance/time = 7000 000/200 000 000 = 0.035 m/year (3.5 cm/year).
202
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Physics TB4
Using waves
Answers
●1 (a)
false
1
(b)
true
1
(c)
false
1
(d)
false
1
(e)
true.
1
●(a) ultraviolet
1
●(b) X-rays
1
●(c) gamma
1
■(d) radio
1
●(e) gamma
1
■(f) infrared
1
●(g) microwaves
1
■(h) visible light.
1
●(a) yes
1
■(b) green roof, low energy loss.
2
2
3
●4 reflected, refracted, diffracted, travel at speed of light, transverse waves.
5
●5 (a)
crust
1
(b)
mantle
1
(c)
magma.
1
■6 All signals pick up noise, analogue noise cannot be distinguished from signal, during
transmission noise is amplified, digital noise can be removed/clear signal.
■7 (a)
(b)
Refraction on entering catseye, total internal reflection at first rear boundary, total
internal reflection at second rear boundary, refraction on leaving catseye.
4
Helps to focus light.
1
◆8 For P wave distance = speed × time = 10t, for S wave distance = speed × time = 6 (t + 600),
10t = 6 (t + 600) 4t = 3600, t = 900s, d = 9000 km.
9
(a)
4
5
Magma from Earth’s interior oozes along mid-oceanic ridges, creates new floor,
spreads away from ridge crest.
4
(b)
Rocks on sea-floor only 180 million years old, other rock fossils much older.
2
(c)
Sea floor older further from ridge crest, oceanic crust sinking into trenches.
2
(d)
Rises.
1
(e)
Mid-Atlantic ridge.
1
(f)
S. America, Africa, India, Australasia, Antarctica.
5
203
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Physics TB5
Radioactivity
Introduction spread
In-text questions
(a)
electron: mass = 0, charge = –1
neutron: mass = 1, charge = 0
proton: mass = 1, charge = +1.
(b)
nucleus.
(c)
proton, neutron.
(d)
Isotope: same number of protons, different number of neutrons.
Atomic number: number of protons in nucleus.
Mass number: number of protons + neutrons/number of nucleons in nucleus.
Spread 5.1
In-text questions
(a)
1.
(b)
3.
(c)
protons = 88, neutrons = 138.
(d)
231
91
4
Pa→ 227
89 Ac + 2 He.
238
92
4
U→ 234
90Th + 2 He.
237
93
4
Np→ 233
91Pa + 2 He.
(e)
+, 2.
(f)
40
17
0
Cl→ 40
18 Ar + −1 e.
66
29
0
Cu→ 66
30 Zn + −1 e.
238
93
0
Np→ 238
94 Pu + −1 e.
■1 (a)
(b)
Gases in the air.
(¾), 75%.
◆2 Evidence of working either by individual decay or total mass number and atomic number
change, 208
82 Pb.
Spread 5.2
In-text questions
(a)
100.
(b)
270 000 000 m/s.
(c)
Reduces to 1/16th.
■1 Beta radiation, small reduction in count rate.
◆2 Alpha radiation – most absorbed by aluminium foil.
Beta radiation – some passed through foil, none through lead.
204
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Physics TB5
Spread 5.3
In-text questions
(a)
approximately 167.
(b)
625.
(c)
15 hours.
(d)
50 hours.
(e)
65 hours.
■1 Activity = number of nuclei which decay ÷ time taken in seconds,
= 36 600 ÷ (10 × 60) = 61 Bq.
◆2 Correctly plotted points, smooth curve, 37.3 minutes.
Spread 5.4
In-text questions
(a)
Gamma radiation too penetrating, not enough change in radiation detected.
(b)
Beta radiation absorbed by aluminium or steel cans, gamma radiation will pass through.
(c)
Relatively constant decay rate to calibrate instrument.
(d)
Does not penetrate as far into the body, causes less damage to patient.
■1 No reading from X to Y, sudden increase at Y, no reading beyond Y.
■2 Source of gamma radiation used, constant reading from X to Y, no reading beyond Y.
◆3 Attack cancer from many directions, each beam does less damage to body on way to cancer.
Spread 5.5
In-text questions
(a)
Plastic would melt/bend in boiling water.
(b)
Animals eat plants.
(c)
Moon formed later than Earth.
■1 They are being applied to the human body so any bacteria in cosmetics could be harmful.
◆2 Over the large timescale involved, the uranium effectively decays to lead with little time
taken in the other decays, enabling comparisons to be made directly between the amounts
of uranium and lead present in a rock sample.
◆3 There may have been quantities of other elements present which have decayed or the final
element in the decay chain may have been present, or the relative compositions may have
been different in the past.
Spread 5.6
In-text questions
(a)
Cancer treatment involves high doses of radiation, damages cells, affects body
processes.
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(b)
Few millimetres of aluminium.
■1 Body still developing, exposure to radiation could damage body too much.
◆2 Reduces it to about 1/100th.
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Radioactivity
Answers
●1 Protons, neutrons (either order), nucleus, electrons, nucleus, positive, negative.
7
●2 Electromagnetic radiation, not particle.
2
●3 More ionising, shorter range.
2
■4 A – false, B – true, C – true.
3
■5 Both have 92 protons, 235 has 143 neutrons, 238 has 146 neutrons.
3
◆6 Count due to radon = 1600 counts per minute, five half-lives reduces to
50 counts per minute, 5 × 56 = 280 seconds.
3
◆7 Alpha radiation short ranged, will not reach body, gamma radiation long range and
penetrates body.
3
Alpha radiation absorbed by tissue in body causing damage, gamma radiation
penetrating and leaves body.
2
■8 Half-life too short.
9
10
1
■(a) Radiation is emitted randomly.
1
◆(b) Average count rate 1086 – 32 = 1054 cpm, constant during the day so half-life much
longer than 24 hours.
3
(a)
Radioactivity from Chernobyl scattered over very large area.
1
(b)
Splitting of the atom into smaller atoms.
1
(c)
When all the uranium has been used up.
1
(d)
Boron.
1
(e)
Acute radiation sickness, death.
2
(f)
Metres of concrete.
1
(g)
Contains more uranium-235 than normal, uranium-235 is fissionable.
2
(h)
More than that is beyond the critical limit, nuclear explosion.
2
(i)
Iodine, caesium.
2
(j)
Thyroid cancer, from iodine.
2
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Introduction spread
In-text questions
(a)
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto.
(b)
Moon.
(c)
Gravity.
(d)
Sources – Star, Sun,
Reflect – Earth, Mars, Moon.
Communication, space research, weather, mapping/surveying, navigation, spying.
(e)
Spread 6.1
In-text questions
(a)
Venus.
(b)
Jupiter, Saturn.
(c)
Smaller, further away.
(d)
Mars and Jupiter.
(e)
Planet – circular, comet – elliptical.
(f)
Stays in same place above Earth.
(g)
Orbits above the North and South poles.
(h)
Distance to Mercury ¼ distance to Mars, inverse square, 4 = 16.
(i)
X at closest distance to the Sun.
2
■1 Points correctly plotted, best line, answer from student’s graph.
◆2 Radius of orbit = radius of Earth + height above Earth = 6400 + 36 000 = 42 400,
circumference = 2␲r, speed = distance ÷ time, = 3 km/s.
◆3 (a)
(b)
Mercury 4.07, Venus 3.03, Earth 2.56, Mars 2.07, Jupiter 1.13, Saturn 0.83, Uranus 0.59,
Neptune 0.47, Pluto 0.41.
1
= 0.06, 0.11, 0.15, 0.23, 0.79, 0.44, 2.83, 4.54, 5.96, points correctly plotted, straight line
speed
graph, passing through origin.
Spread 6.2
In-text questions
(a)
Same number of protons, different number of neutrons in nucleus.
(b)
600 000 000 tonnes per second 600 × 10 × 60 × 60 × 24 × 365 × 10 × 10 tonnes
26
total = 1.9 × 10 tonnes so statement true.
(c)
Formed from material from exploding supernova so had previously been a star.
(d)
Light cannot escape so no reflection.
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■1
neutron star
protostar
red supergiant
red giant
blue supergiant
2
24
white dwarf
6 2
9
◆2 m = E/c = 400 × 10 /(300 × 10 ) , = 4.4 × 10 kg.
Spread 6.3
In-text questions
(a)
Milky Way.
(b)
Blue.
(c)
Blue shift.
(d)
Moving towards us.
(e)
Darker, colder.
■1 Quasars are 12 billion light years away, may be things beyond.
◆2 Able to support life, water, right atmosphere, temperature, form enclosed/artificial
environment.
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Answers
●1 A – false, B – false, C – true, D – false, E – true, F – false, G – false, H – true.
8
■2 Side moving towards us moving faster than whole galaxy moving away, blue shift.
2
■3 A – blue giant, B – red giant, C – white dwarf.
3
◆4 (a)
5
orbit radius = Earth radius + height = 6400 + 350 = 6750 km, circumference = 2␲r = 2␲ ×
6750, = 42411.5 km.
3
(b)
time = distance ÷ speed, = 42411.5 ÷ 7.85 = 5403 s, = 90 minutes.
3
(a)
Meteorite.
1
(b)
3.5 billion years.
1
(c)
16 million years ago.
1
(d)
16 000 years ago.
1
(e)
Buried in ice in Antarctica.
1
(f)
1984.
1
(g)
When Earth and Mars are in correct positions for a space mission.
1
(h)
Samples of magnetite could be produced by bacteria; because of shape chemistry and
environment; on Earth water and chemicals means life, why not elsewhere? Individual
evidence not conclusive; evidence taken as whole could be more so, much work still
needs to be done.
5
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Physics TB7
Using electricity
Introduction spread
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
(j)
Any 5 appliances used in the home e.g. kettle, TV, fire, microwave
oven, CD player.
Any 5 appliances used outside the home, e.g. portable radio, portable
cassette or CD player, torch, car starter motor, mobile phone, electric
train.
An electric current can pass through an electrical conductor but not
through an insulator. Conductors – any metal, such as copper, iron.
Insulators – wood, plastic (for example).
An electric current is a flow of electric charge in a conductor. Unit –
ampere (A).
Voltage is the energy possessed by the charged particles. Unit – volt.
Charge carriers collide with the atoms in the conducting medium.
Unit – ohm.
V = IR I = V/R R = V/I.
R = V/I = 230/10 = 23 ohms.
Thermal energy.
A large current is needed to produce heat.
Spread 7.1
In-text questions
(a)
(b)
(c)
Electrons are removed from the perspex ruler due to friction when
rubbed with the duster. This leaves the perspex ruler with fewer
electrons than normal, so it is positively charged.
Hair becomes charged due to friction with the comb. All the hairs get
the same charge. Like charges repel so the hairs move apart.
If the comb is positively charged it attracts electrons in the paper.
These electrons move towards the top surface of the paper making it
negatively charged. Opposite charges attract so the tiny pieces of
paper move towards the comb, (reverse argument for a negatively
charged comb).
■1 Friction transfers electrons from one part of the film and deposits them on
another part, so parts of the film are positively charged and parts
negatively charged. Opposite charges attract so the film sticks to itself.
■2 The balls have the same charge in equal amounts.
◆3 (a) Electrons move from the comb onto Jaina’s hair. Jaina’s hair gains
electrons so is negatively charged; the comb loses electrons and
becomes positively charged.
(b) Jaina’s hairs all become negatively charged so move apart as like
charges repel.
◆4 (a) The ruler becomes charged (positively) by friction when rubbed on
Alex’s sleeve.The ruler therefore attracts electrons in the water
towards it and the water bends towards the ruler.
(b) Polythene becomes negatively charged. Electrons in the water are
repelled away leaving the water near the rod positively charged.
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Opposite charges attract so the water bends towards the ruler as
before.
Spread 7.2
In-text questions
(a)
(b)
(c)
(d)
Yes. The dust particles would be given a positive charge by the wires
and be attracted to the negatively charged plates.
All the paint particles have the same charge. Like charges repel so the
paint spreads out.This gives an even coating over a wide area on the
article being painted.
The screen becomes charged as the electrons strike it. The charged
screen attracts small dust particles to it as they become charged by
induction.
The inert gas avoids the risk of fire as no oxygen is present and the gas
is unreactive.
■1 Plastic is an insulator so charge can build up on it and may cause a spark,
igniting the fuel. Metal is a conductor so any charge is conducted away.
■2 The car becomes charged by friction with the air as it moves along the
road. The rubber tyres insulate it from the ground so charge builds up.
When you touch the metal car door (a conductor) charge passes through
you giving you an electric shock.
■3 A tree is likely to be the tallest object around so is most likely to be struck
by lightning. If you are standing under the tree you will be electrocuted
also.
◆4 This prevents charge building up on the aircraft. This could cause a spark
that might ignite the fuel. (See answer to Q 2).
◆5 The powder becomes charged by contact with the wire and sticks to the
fingerprint but not to the clean paper.
Spread 7.3
In-text questions
(a)
(b)
(c)
(d)
The ball would oscillate more quickly. (The ammeter would indicate
a larger current.)
Q = It Q = 2A × 60 s = 120 C.
–19
18
1C = 1/(1.6 × 10 ) = 6.25 × 10 electrons.
12 J.
■1 Circuit showing battery and motor in series with current direction from +
to – of battery. Arrows for electrons in opposite direction.
■2 More electrons flowing per second, increased speed of electrons.
◆3 (a) Q = It = 2A × 30 s = 60 C.
(b) Energy, E = VIt = 12 × 2 × 30 = 720 J or 12 V = 12 J/C so energy = 12 ×
60 = 720 J.
(c) Light energy produced = 0.1 × 720 = 72 J.
◆4 (a) So that charges can move over the surface of the ball.
(b) The ball completes the circuit, carrying charge from one plate to the
other. An ammeter connected between one of the plates and the van
de Graaff would indicate a current.
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Spread 7.4
In-text questions
(a)
(b)
(c)
P = VI I = P/V = 1150/230 = 5 A.
To stop the current reaching the appliance.
So that they all get the full voltage, no matter how many lights are
switched on or appliances in use. So that the lights and appliances can
all be switched independently and if a fault occurs in one the
remainder still work.
■1 toaster
power = 230 × 3.5 = 805 W.
kettle
current = 2645/230 = 11.5 A
computer
power = 230 × 0.4 = 92 W.
■2 (a) Cookers require a larger current than the maximum 13 A allowed in a
ring-main.
◆(b) Power = VI = 230 × 30 = 6900 W.
◆3 Ease of adding/removing sockets with minimum of wire.
All appliances in parallel so get the full voltage no matter how many are
switched on (as long as the maximum current of 30 A is not exceeded).
Current to each socket flows by two paths so increasing the
capacity/allowing thinner wire to be used.
◆4 Current in 1 lamp = 60 W/230 V = 0.26 A
No. of lamps = 5/0.26 = 19.
Spread 7.5
In-text questions
(a)
(b)
(c)
A short circuit effectively removes part of the circuit, reducing the
resistance. This increases the current and more heat is produced; this
may cause a fire.
P = VI I = P/V = 920/230 = 4 A 5 A fuse required.
If the fault resulted in a bare wire touching the case, it would become
charged. If someone touched the case, charge would flow through
them, giving them an electric shock.
■1 Water conducts electricity so you could get an electric shock.
There should be no conventional light switches or power sockets in bathrooms.
Lights are switched via an insulating pull cord so the hands are well away from
the electrical connections. The only power socket permitted is a special shaver
point.
■2 TV
0.5 A
3 A fuse
fan heater
5.0 A
13 A fuse
video recorder
0.2 A
3 A fuse
washing machine
12.0 A
13 A fuse
◆3 High-powered appliances are designed to produce heat.
◆4 As the current increases the bimetallic strip gets hotter. Brass expands
more than iron so it bends upwards, past the brass rod, breaking the
circuit. As it cools down it straightens and the circuit breaker can be reset
once the fault has been rectified. (If the bimetallic strip bent the other way
it would reconnect the circuit as it cooled down, like a thermostat.)
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Spread 7.6
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
Energy = power × time = 60 W × (2 × 60 × 60)s = 432 000J (432 kJ).
Energy = VIt = 230 × 10 × (6×60) = 828 000 J (828 kJ).
Lamp – energy transferred = 0.060 kW × 2 h = 0.12 kWh.
Kettle – energy transferred = 2.3 kW × (6/60) h = 0.23 kWh [P = VI =
230 × 10 = 2300 W = 2.3 kW].
6
1 kWh = 1000 W × 3600 s = 3.6 × 10 J.
Cost = 1500 × 10p = £150.
No. of kWh = 1 × 4 = 4 (kWh).
Cost = 4 × 7p = 28p.
■1 appliance
drill
shower
fire
vacuum cleaner
CD player
energy (kWh)
0.45
16
40
0.75
1.2
cost
4.5p
£1.60
£4.00
7.5p
12p
Q2 • energy (J)
6
1.62 × 10
7
5.76 × 10
8
1.44 × 10
6
2.7 × 10
6
4.32 × 10
■3 No. kWh = 0.1 × 7 = 0.7 (kWh).
Cost = 0.7 × 8p = 5.6p.
◆4 Total power = 3.05 kW. No. of kWh used in 5 hours = 15.25.
Cost = 15.25 × 8p = £1.22.
◆5 Compile a table similar to that in Q1 for any choice of 5 appliances.
Add up the individual costs per week.
(Remember this is an estimate so the final answer should be rounded off to
1 or 2 s.f.)
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Using electricity
Answers
●1 electrons, duster, rod, negatively, positively, electrons, insulators, attracts, negatively,
opposite, attract.
●2 (a)
(b)
●3 (a)
(b)
4
11
Dilip became charged by friction with the carpet, the metal door handle conducts
electricity so current passed through him (giving him an electric shock).
3
Electrons were rubbed off the set square due to friction leaving the set square with
less electrons than normal (so positively charged).
3
18022 – 17313 = 709 kWh.
1
709 × 8p = £56.72.
2
●(a) (i)
Green and yellow/earth wire connected to case of microwave oven.
(ii) If the case becomes charged due to a fault, the charge flows down the earth
wire to the ground/causes a large current in live and earth wires so melts fuse,
and user does not get an electric shock.
1
2
■(b) 500 J of energy every second is transferred into other forms.
2
■(c) (i)
2
The fuse melts if the current exceeds 3 A, protecting the appliance.
(ii) P = VI; I = P/V = 500/230; = 2.17 A so 3 A fuse is correct.
■5 vacuum cleaner
electric blanket
lamp
kettle
electric fire
CD player
■6 (a)
750 W
250 W
60 W
3000 W
1000 W
120 W.
3
6
heaters: 4.5 kW × 4 h = 18 kWh
lamps: 0.55 kW × 6 h = 3.3 kWh
total = 21.3 kW.
(b)
3
No. of kWh in 90 days = 21.3 × 90 = 1917 kWh.
Cost = 1917 × 8p = £153.36.
7
2
7
■(a) (i) 3000 J (ii) 3000 J × (2 × 60 × 60)s = 2.16 × 10 J.
3
■(b) No. of kWh = 3 × 2 = 6 (kWh).
1
7
6
◆(c) 1 kWh = 2.16 × 10 J/6 = 3.6 × 10 J.
■8 (a)
(b)
9
10
(i)
2
By friction.
1
(ii) Paint spreads out as like charges repel
2
(iii) Covers large area evenly.
1
To attract the paint so that it sticks well.
2
■(a) Fuse does not melt until current reaches 13 A; Charlie would get an electric shock
at a much smaller current.
2
■(b) Protects the lawn mower/stops it catching fire if a fault occurs.
1
◆(c) (i) 30 mA is much greater than the maximum safe current so it would not be very
safe if this current passed through Charlie.
2
(ii) 30 – 1 = 29 mA.
1
(iii) Resistance of lawn mower is much less than the resistance of Charlie.
1
◆(d) Rubber soled footwear so that Charlie is insulated from the ground and charge
cannot flow to the ground through him.
2
(a)
2
Batteries.
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Physics TB7
(b)
Milkfloats are noted for being slow and having a short range.
2
(c)
(i) Anything sensible – e.g. perimeter of island is about 30 miles so visitor could
do this trip 4 times in 4 days.
2
(ii) Batteries can be recharged easily/overnight.
1
(d)
d.c.
1
(e)
Quiet; no pollution from fumes.
2
(f)
Recharging takes 7 hours/limited range (125 miles); so quiet there is a risk to
pedestrians/horns used as warning adding to noise pollution.
2
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Electromagnetism
Introduction spread
Intext questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
A magnetic material is capable of being magnetised, e.g. iron, steel,
nickel, cobalt. Attract in (i); repel in (ii).
A hard magnetic material is difficult to magnetise but retains its
magnetism, e.g. steel. A soft magnetic material is easy to magnetise
but loses its magnetism as soon as the magnetising force is removed,
e.g. iron.
A magnetic field is an area around a magnet where its effect is felt.
Magnetic induction is when a magnetic material is magnetised by
being placed near to, or in contact with, a magnet. Demonstrate by
picking up a line of pins with a magnet.
(i) Straight wire – circular magnetic field lines in clockwise
direction.
(ii) Solenoid – magnetic field similar to that of a bar magnet with S
pole on LHS.
Pattern remains the same but the direction of the magnetic field is
reversed.
S pole on LHS, N pole on RHS.
(i) iron rod becomes magnetised
(ii) loses its magnetism.
Steel would stay magnetised when the current was switched off.
Electric bell, motor, relay, separating ferrous/non ferrous materials,
moving cars/ferrous scrap around, removing tiny pieces of iron or
steel from the eye.
The core is made from iron so that it loses its magnetism when the
current is switched off.
Spread 8.1
In-text questions
(a)
(b)
(c)
(d)
Because the wire is flung out of the magnetic field like a stone from a
catapult.
The direction of the force would be unchanged.
Check that Fleming’s left-hand rule can be applied correctly.
A larger current will produce a louder sound.
■1 Arrow upwards.
(i) Stronger magnet/bigger current.
(ii) Reverse the current direction/swap over the magnetic poles.
■2 (a) Bigger force on the wire.
(b) Smaller force on the wire.
(c) Wire would oscillate as the direction of the force would change at the
same frequency as the applied a.c.
◆3 Force on wire less (sin x dependence).
◆4 Frequency of a.c. current in coil increases, but size of current is unchanged.
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Spread 8.2
In-text questions
(a)
(b)
(c)
Use Fleming’s left-hand rule to check that the forces on the coil are as
indicated.
Because the direction of the forces on the coil reverse as it passes the
vertical, so it would then rotate in the other direction.
The iron core becomes magnetised and increases the magnetic field.
This gives a bigger force on the coil/makes the motor more powerful.
■1 E.g. Washing machine, electric sewing machine, dishwasher, food
processor, hair dryer, tumble dryer (any two).
■2 (a) The motor would rotate in the opposite direction.
(b) The motor would be more powerful/rotate faster.
◆3 Yes. An electromagnet, if connected to a d.c. supply, produces a magnet
with poles dependent on the current direction in the coil of the
electromagnet.
◆4 Several coils – each will have the maximum force on it at different times
so the average force due to all the coils will be approximately constant.
Radial magnetic field – the sides of the coil are always perpendicular to the
magnetic field as the coil rotates so the force on the coil is constant.
Spread 8.3
In-text questions
(a)
(b)
(c)
The direction of the force on the electrons is reversed.
(i) The deflection of the meter (i.e. induced current) would reverse
(i.e. to left).
(ii) The deflection would be as in (b) (i) (i.e. to left).
(iii) An alternating current would be induced.
If the current flows in a clockwise direction when looking at the end
of the coil that end is a S pole, if the direction is anticlockwise, a N
pole. (Or alternative rule if preferred.)
■1 (a) The direction of the induced current reverses.
(b) The induced current is smaller.
(c) No induced current (no magnetic field lines are being cut by the wire).
■2 Increases as magnet approaches coil, drops to zero when magnet is inside
coil, increases in the opposite direction as magnet leaves coil with slightly
bigger magnitude since the magnet is moving faster.
◆3 Induced current increases as the car enters the tunnel, falls to zero when
completely inside it, has a maximum value in the opposite direction as the
car starts to leave the tunnel, gradually reducing to zero when it is well
away from the tunnel.
If speed is doubled the magnitude of the induced current is doubled (and
the time scale is halved, but this is not shown on a graph of induced
current against position).
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Spread 8.4
In-text questions
(a)
(b)
(c)
(d)
(e)
Check correct use of Fleming’s right-hand rule.
More powerful magnets/more turns on the coil/wind coil on iron core.
(Any two.)
The change of current is in opposite directions (increasing/decreasing
currents).
Current reaches a constant value.
The current is constantly changing in magnitude and direction.
■1 The faster he pedals the greater the induced voltage and the greater its
frequency.
■2 Double the output.
◆3 (a) Same frequency, greater magnitude.
(b) Half the frequency, smaller magnitude.
◆4 When giving current forces act on the sides of the coil which oppose the
motion and tend to slow down the rotation of the coil.
Spread 8.5
In-text questions
(a)
(b)
(c)
(d)
Vp
VS
=
Np
NS
230 9200
=
NS
10
NS = 400.
230 × IP = 10 × 5
IP = 0.22 A.
VPIP = VSIS
2
Heat loss = I R so for a given current R must be reduced.This can be
done by using a wire of a material having a low resistance and/or
using a thicker wire.
A laminated core increases the resistance of the core so eddy currents
are reduced. If R increases, I decreases for a given V.
■1 It is a step-down transformer with a turns ratio (Np/NS) of 230/12.
■2 A transformer needs a changing magnetic field so that a voltage is induced
in the secondary coil. Only an a.c. supply will provide a changing magnetic
field in the core.
◆3 80 10 V 12 000.
◆4 (a) Np:NS = 230:9
(b) Power = V × I = 9 × 2 = 18 W
(c) 18 = 230 × IP IP = 0.078 A.
Assumption – transformer is 100% efficient.
Spread 8.6
In-text questions
(a)
(b)
(c)
(d)
To provide a direct current; essential for the electromagnet.
A lot of water is needed for cooling.
Ice caps will melt causing flooding.
Climate changes affecting economies and lifestyles of various
countries.
Visual pollution as they are usually in areas of natural beauty.
Artificial lakes flood land so that houses and farms may be lost and
they also alter the habitat of plants and animals.
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Physics TB8
■1 So that it reaches a higher temperature and provides more KE to turn the
turbines.
■2 E.g. Tidal barrier – flooding of land adjacent to the river estuary and
changes to habitat for wildlife. Wind turbines – take up a lot of room, are
thought by many to be unsightly and make a lot of noise.
◆3 Wind farms take up a lot of space and there is not much spare land in this
country, but land is more widely available in developing countries.
Suitable sites need to have a lot of wind, for instance, in coastal regions or
on high ground. The specific country would need to be considered to
compare this.
Visual and noise pollution is a problem in this country but is less likely to
bother people in a developing country where other energy sources may not
be available and the land may not be as densely populated.
(This is an open-ended question which lends itself to research and
discussion.)
◆4 Points to be considered include:
Will our energy requirements increase, decrease, stay the same?
The need to develop alternative energy sources as fossil fuel supplies
run out.
Pollution associated with the burning of fossil fuels.
Suitable alternative sources for this country – HEP, wind, tidal, wave – and
locations.
Pollution associated with alternative sources.
The pros and cons of nuclear power.
Measures to save energy.
Spread 8.7
In-text questions
(a)
6
3
P = VI I = P/V = 25 × 10 /25 × 10 = 1000 A
2
3 2
7
Power wasted = I R = (1 × 10 ) × 10 = 1 × 10 W.
6
4
(ii) I = 25 × 10 /25 × 10 = 100 A
2
5
Power wasted = (100) × 10 = 1 × 10 W.
(i)
■1 (a)
(b)
■2
◆3
◆4
◆5
To keep warm.
Both feet are at the same voltage so no current flows from one foot to
the other through the bird.
High voltage is necessary so that the current is kept as low as possible
(P = VI so large V means small I).This minimises heat losses in the power
2
lines; heat lost = I R so it is important that I is small.
We need to increase and decrease the voltage before and after power
transmission (see answer to Q2). Transformers are used to do this and they
only work with an alternating current, (d.c. voltages can be changed, but it
is difficult to do so).
Power loss reduced by a factor of 10. But low resistance wires would be very
thick so would need more support as they would be heavier. They would
also be more costly to produce as they would use a greater quantity of metal.
(a) Current much less at 230 000 V (1 A instead of 1000 A) so much less
2
2
energy wasted as heat. Power loss = I R. This is dependent on I so it
is very important to keep the current as low as possible.
(b) Step down transformer with turns ratio of 1000:1 or by reducing the
voltage in stages.
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Physics TB8
Electromagnetism
Answers
●1 (a)
●2 (a)
commutator (b) rotates
(f) alternating voltage.
(c) magnetic field
(d) transformer
(e) brushes
6
current direction correct (from left to right between poles).
1
(b)
Magnetic field – shape; direction from N to S.
2
(c)
Up.
1
◆3 A transformer is used to step up the voltage for transmission around the country. This
2
reduces the current (I = P/V) keeping energy losses (= I R) to a minimum.
3
■4 (a)
1.5 (A), –2.6 (A), –1.5 (A).
3
(b)
Graph – axes (quantity and unit), scales, plots, curve.
4
(c)
a.c. as it has + and – values.
2
◆(d) (i)
5
(a)
(b)
(c)
Larger current values, same frequency.
2
(ii) Larger current values, twice the frequency.
2
●(i) To the left.
1
■(ii) The coil carrying a current is in a magnetic field,
so there is a force on it given by Fleming’s left-hand rule.
2
●(i) Vibrates.
1
■(ii) a.c. keeps changing direction. As the current direction changes the direction
of the force on the coil changes.
2
■(i) The paper cone vibrates through a bigger amplitude.
■(ii) The sound is louder.
◆6 (a)
(b)
6
2
3
I = P/V = (25 × 10 )/(400 × 10 ) = 62.5A.
3
High voltage means low current so energy losses are kept as small as possible
2
(c)
7
8
P = VI and heat loss = I R.
3
Voltages need to be stepped up and down using transformers which only work on a.c.
2
■(a) Clockwise, FLHR shows that there is a force up on the side PQ and down on RS
forming a couple which turns the coil clockwise.
4
◆(b) Commutator reverses the direction of the current in the coil each time the coil
passes the vertical so that the forces on the coil are always in the same direction
to keep it rotating.
3
◆(c) Bigger current/voltage, more turns on the coil, more powerful magnets, wind coil
on iron core (any three).
3
◆(d) More sets of coils, bigger current/voltage, more powerful magnets (possibly
electromagnets), radial magnetic field, more turns on the coil, use of iron core
(any three).
3
◆(e) (i)
2
(a)
Needle moves back and forth indicating an alternating current.
(ii) + and – in shape of a cosine wave (starting at a maximum); one complete cycle.
3
(iii) When PQ moves up through the magnetic field a current is induced in one
direction and when it moves down the current is in the opposite direction;
there is no induced current when the coil is vertical as it is not cutting the
magnetic field lines; it has its maximum value when the coil is horizontal/when
the magnetic field, sides of the coil and direction of movement are all mutually
perpendicular.
3
Convection.
1
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Physics TB8
(b)
Wind turbines – wind turns the turbines to make electricity.
Fan – uses electricity to turn the blades of the fan making a wind.
2
Greater wind speed gives the turbine more KE so generator gets more KE to
produce electricity.
2
(d)
Need lots of wind so near the coast and on high ground.
2
(e)
New lightweight materials used in the wind turbines, better electrical generating
products.
2
Wind strikes the blades of the wind turbine giving them KE. This KE is used to
turn the turbine connected to a generator which rotates magnets around a fixed
coil inducing a voltage in the coil.
4
(c)
(f)
2
KE = 1/2mv ; if v doubles, the KE increases by a factor of 4 since v is squared;
the mass of air striking the blades of the wind turbine every second also doubles
so the KE is 8 times larger.
4
(h)
Supplies of fossil fuels are running out; we are using more and more electricity.
2
(i)
Nuclear/HEP/wind/wave/tidal/solar/biomass/geothermal (any three).
3
(j)
Does not produce acid rain/contribute to the greenhouse effect/renewable/does
not use fossil fuels which are in short supply/wind is free (any two).
2
Wind does not always blow/noisy/need a large number to produce a reasonable
amount of electricity/occupy a large area/visual pollution/few ideal sites/usually
in areas of natural beauty (any two).
2
(g)
(k)
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Physics TBA1
Introduction spread
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
R =230/0.5 = 460 Ω.
(i) V = 125 V (ii) 15 C.
(i) V = 8 V (ii) 4 V (iii) 2 Ω.
(i) Resistor whose resistance changes with the light intensity falling
on it.
(ii) Resistor whose resistance changes with temperature.
(i) Lamp will go out.
(ii) The ammeter reading increases because closing the switch
short-circuits the lamp, reducing the effective resistance in the
circuit.
(i) 3A (ii) 13 A.
Iron is easily magnetised but loses its magnetism as soon as the
current is switched off.
Spread 1.1
In-text questions
(a)
(b)
(c)
(Check the truth table is correct).
(Check the truth table is correct).
OR gate.
■1 ball
cube
outcome
red
red
lose
red
blue
lose
blue
red
lose
blue
blue
win
AND logic.
■2 NOT
◆3 AND
◆4 NOT; add an AND gate with the other input connected to a moisture sensor.
Spread 1.2
In-text questions
(a)
(b)
(c)
(d)
(e)
Temperature and moisture sensors.
OR.
Current in coil magnetises the two parts of the reed so that they
attract each other, completing the circuit.
To keep the current low so that the LED is not damaged.
R = 3/0.020 = 150 Ω.
■1 Temperature and moisture sensors.
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Physics TBA1
■2 (a)
◆3 (a)
(b)
◆4 (a)
(b)
The voltage is too high. (b) Use a relay between the logic gate and the
lamp.
Light (LDR) and temperature (thermistor) sensors.
Heating runs off the mains electricity supply so will be 230 V, much
too high for a logic gate.
I = V/R = 3.5/175 = 0.02 A(20 mA).
R = V/I = 1.5/0.02 = 75 Ω.
Spread 1.3
In-text questions
(a)
(b)
Thermistor.
Bell.
■1 (i) thermistor (ii) buzzer/bell (iii) OR gate.
■2 living room
bedroom
pump
off
off
off
off
on
on
on
off
on
on
on
on
input – thermostats, processor – OR gate, output – hot water pump.
◆3 door 1
door 2
alarm
closed
closed
off
closed
open
sounds
open
closed
sounds
open
open
sounds
processor – OR gate
◆4 Inputs – switch which is closed when seat belt is done up, pressure switch
which is closed when seat is occupied.
Output – alarm in form of bell/buzzer/indicator lamp on dashboard.
seat belt
seat
alarm
seat belt
seat
alarm
open
open
off
0
0
0
open
closed on
0
1
1
closed
open
off
1
0
0
closed
closed off
1
1
0
Need to add a NOT gate to the seat circuit; this gives the inverse of an OR
gate, so place another NOT gate in the output circuit.
seat belt
seat
seat NOT
OR out
NOT
0
0
1
1
0
0
1
0
0
1
1
0
1
1
0
1
1
0
1
0
Spread 1.4
In-text questions
(a)
(b)
(c)
224
Check agreement with truth table.
Check agreement with truth table.
C
D
1
0
1
1
0
0
0
0
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?
Physics TBA1
(d)
(e)
(f)
(g)
(h)
To detect body heat.
To reverse the light sensor output, making it ‘high’ in the dark.
Lamp needs larger current than the logic gate.
C
D
0
S
(1)
1
1
0
(1)
1
0
1
0
0
1
1
(see diagram)
R
0
(0)
1
(0)
1
(0)
1
(1)
1
Q
(1)
P
■1 NOT
■2 A
0
0
1
B
0
1
0
C
0
1
1
D
1
0
1
out
0
0
1
1
1
1
0
0
◆3 (see diagram)
◆4 A = 1 B = 0 C = 0
S
R
0
1
(0)
0
(1)
1
(1)
1
(1)
1
(0)
1
(0)
out
Spread 1.5
In-text questions
(a)
(b)
(c)
(d)
(e)
Bistable unit using two NAND gates.
Latch using two NAND gates.
NOR
inputs output
0
0
1
0
1
0
1
0
0
1
1
0
Use of NOR gate truth table to check
logic of bistable.
Use of NOR gate truth table to check
logic of latch.
Make R high momentarily.
LDR
bell
thermistor
Pressure
pad 1
Pressure
pad 2
alarm
Light
sensor
■1 Input R must go high.
◆2 NAND 1 R1 other input 1
NAND 2 S1 other input 0
Output 1
R connected to low voltage, output becomes 0.
◆3 Connect input S of a latch to the doorbell so that S goes high if the bell rings.
This will set the latch until Steve resets it.
◆4 Latch circuit with S connected to the ‘on’ switch and R to the ‘off’ switch.
Spread 1.6
In-text questions
(a)
(b)
4 V.
Decreases.
225
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?
Physics TBA1
(c)
(d)
(e)
(f)
(g)
As R1 increases, voltage across it increases, output voltage decreases.
To switch off lamp when it becomes light.
Switch on lamp when it gets light.
Reverse positions of thermistor and resistor.
2 V.
■1 dark
low
light
high
■2 Output voltage = 5 V at A decreasing to 0 V at B
◆3
45⍀
12V
15⍀
3V
◆4 (i) 1V (ii) 160 ohms (iii) V across BC increases; V across AB decreases
Spread 1.7
In-text questions
R
V
R + RLDR in
(a)
Vout =
(b)
(c)
Reverse positions of thermistor and resistor, R.
Reverse positions of thermistor and resistor, R on top input to AND
gate, change AND gate for OR gate.
Decrease.
(d)
■1 (a)
dark
A B
C (b) AND gate
(c)
A B
C During the day the LED does
0
0
0
light
0
0
0
not glow whether S is pressed
0
1
0
0
1
0
or not. LED comes on when
light
1
0
0
dark
1
0
0
it is dark but goes out if S is
1
1
1
1
1
1
pressed.
■2 (a) To switch on a large current to operate the buzzer and stop the
machine.
(b) A B
C BUZZER
0
0
0
0
0
1
1
1
1
0
1
1
1
1
1
1
Buzzer sounds when light fails to reach one or both LDRs, i.e., if bars
are too long.
(c) NAND gate, so buzzer sounds, when light reaches both LDRs.
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Physics TBA1
Answers
●1 (a) low (b) high (c) low.
2
●(a) 0
0
0
0
1
0
1
1
0
1
0
1
■3 (a)
(b)
(c)
3
●(b) AND.
■(c) E.g. Seat belt warning system, safety system for
opening a safe in a bank.
LDR and resistor connected as a potential divider with a voltmeter across the resistor.
3
In the light the resistance of the LDR is low, so the voltage across it is low therefore
the voltage across the resistor, and the voltmeter reading, are high. When the light
intensity is less, the voltage across the LDR increases and the voltmeter reading
decreases.
3
Read voltmeter for known light intensities; and mark scale.
2
■4 Record and play buttons as inputs to AND gate, start switch connected to output.
◆5 D
E
F
G
1
1
1
0
0
1
1
0
1
1
0
1
0
0
1
1
1
1
0
1
0
1
1
0
1
1
1
0
0
0
1
1
◆6 (a)
(i) in dark room (ii) on outside of door.
2
(b)
V at X = (1800/2000) × 6 = 5.4 V
3
(c)
Yes, large voltage across it.
(d)
New V at X = (1800/2000 000) × 6 = 5.4 × 10
(e)
(i)
2
–5
V, very small so LED not on.
Mains lamp requires a much higher voltage than the LED.
4
1
3
■(a) AND gate.
1
■(b) Output of AND gate not large enough to power alarm; relay used to switch on a
large voltage supply for alarm.
2
■(c) Alarm stops as one input to AND gate now low.
2
(d)
8
4
4
(ii) Relay placed between X and mains lamp. Low voltage from X switches on relay
which in turn switches on a large mains voltage for the lamp.
7
4
■(i)
A circuit in which the output is locked into one state, high or low, until it is reset. 2
■(ii) Alarm will keep ringing even when a burglar steps off the doormat.
2
◆(iii) (see diagrams – figs 49, 50).
6
(a)
Low power, less dispersion/emits light of a single colour.
2
(b)
Low power so less energy wasted.
2
(c)
(i)
2
(d)
To prevent too large a current damaging the LED.
(ii) V across R = 5 – 1.7 = 3.3 V, R = 3.3 V/20 mA = 165 ohms.
3
(i)
2
Large reverse voltage when reverse biased.
(ii) Diode in parallel with LED and facing the opposite way,
227
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Physics TBA1
diode conducts better than LED when LED is reverse
biased so current goes through diode.
(e)
(i)
4
LED – light emitted when diode conducts a current,
photodiode – current produced when light shines on it,
arrow directions on symbols show light away from or
towards the diode symbol.
(ii) Straight line through the origin.
2
(iii) In the light; low resistance so current is high.
(iv) Smallest output voltage = 10
228
–9
3
6
A × 10 Ω = 10
–3
3
V (1 mV).
3
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Physics TBA2
Processing waves
Introduction spread
In-text questions
(a)
wavelength
amplitude
(b)
Equal to, less than, greater than.
(c)
A more dense than B, angle of refraction > angle of incidence, B more dense than C,
angle of refraction > angle of incidence, A glass, B water, C air.
(d)
(i)
5 Hz.
(ii) Speed = frequency × wavelength, 5 × 0.3 = 1.5 m/s (150 cm/s).
Spread 2.1
In-text questions
(a)
(b)
300 000 000/200 000 000 = 1.5.
1.5, same.
(c)
Refraction at first surface, dispersion at first surface, refraction at second surface,
further dispersion at second surface, red → violet (red refracted least).
◆1 (a)
Calculation of sine i – 0.174 0.342 0.500 0.643 0.766 0.866 0.940
calculation of since r – 0.122 0.259 0.375 0.485 0.574 0.616 0.707
axes labelled, suitable scale, points correctly plotted.
(b)
Straight line, through origin, omitting anomalous point.
(c)
38, 41.
(d)
Slope of graph used, 1.33.
(e)
300 000 000/1.33 = 226 000 000 m/s.
◆2 Refractive index = sine 90/sine c, sine c = sine 90/refractive index.
Glass sine c = 1/1.5 = 0.6667, c = 41.8°.
Water sine c = 1/1.3 = 0.7692, c = 50.3°.
Spread 2.2
In-text questions
(a)
Light from distant object almost parallel, to pass through focal point.
■1 (a)
(b)
◆2 (a)
75 mm.
Nothing.
Suitable scale, 2f and f correctly positioned, ray parallel to axis passing through f, ray
through optical centre undeviated, image is at 2f, real, inverted, same size.
229
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Physics TBA2
(b)
through optical centre undeviated, image is beyond 2f, real, inverted, magnified.
Spread 2.3
In-text questions
(a)
Ray diagram with object well beyond 2f, second ray diagram with object closer to lens
but image in same place, comment on how lens moved further away from film.
(b)
Suitable explanation involving timing of beam, echo principle.
(c)
To make image right way up.
(d)
Stop light being ‘wasted’/make image brighter.
(e)
Focal length, light parallel after passing through lens.
◆1 (a)
through optical centre undeviated, image is at 180 cm.
(b)
Decreased.
(c)
Larger.
◆2 (a)
(b)
Lens only move a short distance in and out for the range considered.
Image becomes blurred.
Spread 2.4
In-text questions
(a)
(i)
2.23, 1.62, 1.35, 1.18, 1.07.
(ii) Axes labelled, suitable scale, points correctly plotted, smooth curve.
(iii) Greater mass reduces frequency.
◆1 Alters the wind flow so not all in same direction at same speed, reduces chance of resonance.
Spread 2.5
In-text questions
(a)
Transverse.
(b)
2.4 m.
(c)
523.2, 784.8.
■1 Mid-point produces note with one antinode at mid point, quarter way along produces
note with two antinodes at ¼ and ¾ along length, double the frequency.
◆2 Axes labelled, suitable scale, points plotted, straight line, passing through origin.
Spread 2.6
In-text questions
(a)
1288 mm.
(b)
Open tube has antinode at each end, closed tube has node at one end.
230
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?
Physics TBA2
(c)
Closed pipe has antinode at open end, node, another antinode, node at closed end.
Open pipe has antinode at open end, node, another antinode, another node,
antinode at closed end.
◆1 Pitch gets higher.
◆2 l/f calculated as 0.00390, 0.00347, 0.00313, 0.00293, 0.00260, 0.00234, 0.00208, 0.00195.
␭ calculated as 1288, 1144, 1032, 968, 860, 772, 688, 644 mm.
Axes labelled, suitable scale, points correctly plotted, straight line, through origin,
slope = 330 000 mm/s (330 m/s), speed of sound.
Spread 2.7
In-text questions
(a)
␭ = 330/256 = 1.29 m, whole wavelength difference at X, so 1.29 m.
(b)
½ wavelength difference at Y, so 0.64 m.
(c)
446 Hz, tightening string increases frequency, increasing beat frequency means
getting further away from tuning fork frequency.
(d)
Wavelength of microwaves much larger.
◆1 Wavelength of the light used is very short, large distance needed to make the distance of
band from central large enough to measure.
Spread 2.8
In-text questions
(a)
Wave.
(b)
They are undeviated, no diffraction occurs.
231
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Physics TBA2
Processing waves
Answers
●1 A – false, B – false, C – true, D – false, E – true, F – true, G – false.
7
●2 300 000/1.2, 250 000 m/s.
2
■3 (a)
Infrared.
1
Ultraviolet.
1
(b)
◆4 Suitable scale, 2f and f correctly positioned, ray parallel to axis passing through f,
Ray through optical centre undeviated, image at 13 cm – 14 cm, real, inverted,
3 cm – 3.5 cm tall.
8
■5 Move it towards film.
2
●6 (a)
Parallel rays from Sun, focused onto paper.
2
35 cm.
1
(b)
●7 5 cm, shortest focal length.
2
■8 Refraction at both surfaces of first lens, refraction at both surfaces of second lens,
focused on retina.
3
■9 In step could lead to forced vibration, at resonant frequency bridge vibrates and collapses.
3
10
■(a) Thinner string produces higher note.
1
◆(b) Shorten length, increase tension.
2
◆(c) Different quality or shape of note.
1
◆11 ␭ = 4 × 25.8 = 103.2 cm = 1.032 m, f = v/␭ = 330/1.032 = 320 Hz.
3
◆12 Distance from car to radio masts changing.
13
When path difference equal to whole wavelengths constructive interference and louder,
when path difference equal to odd half wavelengths destructive interference and quieter.
3
(a)
Reflected light is polarised in one direction.
1
(b)
Only allow light vibrating in one direction through, at right angles to reflected
light’s vibration.
2
(c)
Transmitted light not polarised, some vibration in same direction as polarising filter.
2
(d)
Particle does not vibrate, waves vibrate, particle would go through filter, wave
would not go through filter at right angles, polarisation supports wave behaviour.
5
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Physics TBA3
Introduction spread
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
Distance from pivot to man is large so force required is small for a
given moment.
8.33 m/s.
30 m/s.
750 N.
Backward force is greater than forward force, force down greater than
force up.
(i) 240 000 J.
(ii) 4000 N.
Air resistance increases as velocity increases. Eventually air resistance
force upwards is equal to weight of parachutist downwards so velocity
becomes constant – terminal velocity.
Double glazing, loft insulation, lagging hot water tank, cavity wall
insulation, carpets/curtains… (any three).
64%.
Spread 3.1
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
2
1.25 m/s .
2
2 m/s .
(i) Graph – line through (2, 0) of gradient –10 cuts velocity axis at (0,20)
and (4, –20), maximum height = 20 m.
(ii) Displacement = zero.
(iii) Positive and negative areas of graph are equal.
( u + ( u + at))t
2
s = ut + 21 at
2
v + u = 2s/t v – u = at (v + u)(v – u) = 2s/t × at = 2as
60 m/s, 900 m.
(i) 7.2 m (ii) 1.2 s (iii) 2.4 s.
s=
2
2
v = u + 2as
■1
■2
◆3
◆4
2
Steady acceleration of –0.5 m/s , time to stop = 100 s.
2
2 m/s .
576 m.
(a) 5 s, (b) 50 m/s, (c) 11.25 m/s.
Spread 3.2
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(i) 15 m (ii) 30 m (iii) 60 m.
Check values on graph.
Both fall the same vertical distance each second.
Same time as before.
It would go twice as far horizontally in each second.
Less than 45° – large horizontal component of velocity but short time
of flight (does not rise very high); more than 45° – small horizontal
component of velocity but long time of flight. 45° is half-way between
0 and 90°, giving maximum range.
233
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Physics TBA3
2
■1 Gravity pulls the dart downwards with an acceleration of 10 m/s .
Dart follows parabolic path.
■2 0.5 s.
◆3 (a) 3 s (b) 45 m.
◆4 1000 m.
Spread 3.3
In-text questions
(a)
(b)
(c)
(d)
(e)
20 000 kg m/s.
520 kg m/s.
8 m/s, 0.8 m/s.
15 m/s.
0.6 m/s to right.
◆1 Since there was zero momentum before Chris moved, his momentum
towards the jetty equals the momentum of the boat away from the jetty.
◆2 400 m/s.
7
◆3 2 × 10 m/s.
◆4 F = 250 N when she bends her knees, 25 000 N when she does not.
Spread 3.4
In-text questions
(a)
(b)
(c)
Mass decreases as fuel is used up, gravitational field strength
decreases as height increases.
No forces acting on the rocket so it will maintain a constant velocity.
2 m/s.
■1 A rocket carries its own oxygen supply, a jet plane does not.
2
■(a) S answer. The water escaping from the open end of the bottle gives a
force on the bottle in the opposite direction, so it rises (Newton’s
third law).
H answer. The momentum of the water downwards is equal to the
momentum of the rocket upwards, so the rocket rises.
2
◆(b) (i) 50 m/s (ii) Acceleration decreases because the mass of water
ejected per second and its velocity decreases. The unbalanced force (or
momentum of the rocket) decreases at a faster rate than accounted for
by the decrease in mass, so the acceleration decreases.
◆3 No momentum before the balloon is released, so the momentum of the air
molecules in one direction is equal to the momentum of the balloon in the
opposite direction.
◆4 1 280 000 N.
234
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Physics TBA3
Spread 3.5
In-text questions
(a)
(b)
(c)
The cars have much more kinetic energy to be converted into other
forms on impact. The deceleration is greater when the speed is higher,
so the force on the occupants is greater.
The person would be stopped very quickly causing a large deceleration
and so a bigger force.
Large area so that the pressure (= force/area) on the child’s body is
less, reducing the risk of serious injury.
■1 (a)
To stop you being thrown forward at high speed, possibly through the
windscreen.
(b) So that back seat passengers cannot be thrown forward and strike the
driver.
■2 The front and rear sections are designed to crumple in an accident,
stopping the car more slowly and reducing the force on the occupants –
crumple zones. The passenger compartment is very strong so that the
passengers are not crushed.
◆3 The rapid deceleration that occurs in an accident inflates the airbag very
rapidly. This protects the driver from injuries caused by the steering wheel
etc. being forced against him.
◆4 (a) 8 m/s.
(b) 200 000 J.
(c) 80 000 J.
(d) 120 000 J.
(e) 8400 J.
(f) 4200 N. Suitable comment – e.g. if she had moved a shorter
distance/the seat belt had been tighter, the force on her would have
been greater.
Spread 3.6
In-text questions
(a)
(b)
(c)
(d)
(e)
1008 000 J.
91 200 J.
601 200 J.
Aluminium has a high specific heat capacity, so requires more energy
to heat it than other metals such as copper, making it more expensive
to use. Also it is not such a good conductor of heat as copper so it
would take longer for the water to be heated.
Too high.
■1 iron (9000 J) [lead – 7560 J].
■2 Water has a very high SHC so can absorb a large amount of energy without
raising its temperature very much.
◆3 Treacle has a higher SHC than sponge so absorbs a lot more energy.
It therefore takes longer for its temperature to fall on cooling as it has
more energy to lose.
◆4 500 J/kg°C.
235
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Physics TBA3
Spread 3.7
In-text questions
(a)
(b)
(c)
(d)
(e)
(f)
(g)
Reduces energy wasted due to friction.
Temperature is related to molecular movement. Water molecules are
moving faster at the bottom of the waterfall than at the top, so the
water temperature is higher.
600 000 J.
420 000 J.
0.2°C.
Temperature rise unchanged. GPE and so thermal energy produced per
second halved, but energy required to heat water halved also. 70% of
⍜
mgh = mc so m’s cancel.
45%.
■1 32% Energy wasted as heat (due to friction), sound etc.
■2
energy source
advantages
disadvantages
solar energy
fuel is free
Sun does not always shine
useful in hot countries
cover large area to produce power
equivalent to a small power station
wind energy
fuel is free
wind does not always blow
does not pollute atmosphere
visual and noise pollution
cover large area to produce power
equivalent to a small power station
geothermal
free energy
only possible in certain places
non polluting
expensive to drill down several km
◆3 1600 W.
◆4 Any relevant points.
e.g.
236
petrol engine
electric motor
fuel readily available
greater range on full tank
high top speed
pollutes environment
noisy
need recharging facility
limited range
lower top speed
little/no pollution (but pollution at power station)
quiet
M
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Physics TBA3
Answers
●1 (a)
2
Acceleration (b) temperature (c) parabola (d) rocket.
4
■(a) v = u + at, t = (v – u)/a = 50/2.5 = 20 s (or acceleration = velocity change/time).
(b)
2
3
2
◆(i) v = u + 2as, 2500 = 0 ± (2 × 2.5 × s), s = 500 m.
3
◆(ii) motorist travels 40 × 20 = 800m.
2
■(c)
5
50
P
40
S
30
20
10
0
time in s
20
◆(d) Area under graph for P from t = 0 to t = 20 s = ½ 50 × 20 = 500 m.
2
◆(e) When they meet, after time T, the area under each graph is the same.
40 × T = 500 + 50 (T – 20), T = 50 s.
3
4
⍜
■(a) Q = mc = 2 × 380 × 500 = 380 000 J.
(b)
3
2
■(i) Q = mc = 70 × 800 × 30 = 1680 000 J.
3
◆(ii) Concrete stores more energy as it takes more energy to heat it up/has greater SHC.
This means it releases more energy as it cools down.
3
■(c) E.g. Low density, low thermal conductivity, traps air, inert, not flammable.
4
2
2
■(a) KE = ½ mv = ½ × 80 × 20 = 16 000 J.
3
◆(b) WD = KE lost, F × 160 = 16000, F = 100 N.
3
◆(c) F × 1.6 = 16 000, F = 10 000 N.
2
◆(d) 4 times bigger/F becomes 40 000 N.
2
v doubled so KE (= ½ mv ) increases 4 times, so braking force is 4 times bigger.
2
◆(e) Engine compartment crumples in an accident so the car stops more slowly and the
force on the occupants is less. Reference to F = ma or Ft = mv – mu. Passenger
compartment strong so does not crumple.
5
(a)
●(i)
6
3
6
Weight vertically downwards = 30 × 10 N, thrust vertically upwards = 33 × 10 N. 3
6
■(ii) Resultant force = 3 × 10 N.
6
1
6
2
◆(iii) F = ma, 3 × 10 = 3 × 10 × a, a = 1 m/s .
(b)
■(i)
3
Mass lost = 14 000 × 2 × 60 = 1680 000 kg.
6
6
2
6
■(ii) Mass after 2 minutes = 3 × 10 – 1.68 × 10 = 1.32 × 10 kg.
6
●6 (a)
6
6
1
2
◆(iii) F = ma, 33 × 10 – 13.2 × 10 = 1.32 × 10 × a, a = 15 m/s .
3
◆(iv) Gravitational field strength decreases with height.
1
Renewable energy extracted from the environment; not used up, so always available
to us. E.g. wind, wave, tidal, HEP, solar, geothermal, biomass (any two).
Non-renewable – once they are used they are gone for ever. E.g. coal, gas, nuclear
(any two).
(b)
(4)
Answers will depend on the examples given in (a).
Renewables – see Spread 7, question 2.
Non-renewables – advantages could include availability currently, small space
occupied for the amount of energy produced, well established technology.
237
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Physics TBA3
Disadvantages could include pollution – acid rain, global warming, limited supplies.
Nuclear – radiation hazards/accidents/decommissioning.
7
6
■(a) 0.5 kg – energy = mcθ = 0.5 × 4200 × 80 = 168 000 J.
1.0 kg – energy = mcθ = 1.0 × 4200 × 80 = 336 000 J.
1.5 kg – energy = mcθ = 1.5 × 4200 × 80 = 504 000 J.
6
◆(b) 0.5 kg – efficiency = energy output/energy input × 100 = 168/200 × 100 = 84%.
1.0 kg – efficiency = energy output/energy input × 100 = 336/380 × 100 = 88%.
1.5 kg – efficiency = energy output/energy input × 100 = 504/540 × 100 = 93%.
◆(c) The energy required to heat the kettle stays the same.
2
◆(d) Energy required to heat the kettle/element, energy lost to surroundings.
2
◆(e) Energy transfer is very efficient, efficiency increases as the mass of water increases,
as the energy used to heat the kettle, etc., becomes a smaller proportion of the total
energy input.
3
◆8 (a)
9
6
s=
1
2
2
at (u = 0) 0.128 =
1
2
× 10 × t
2
t = 1.16 s
3
(b)
Fiona is expecting the ruler to be dropped/is prepared to catch the ruler.
2
(a)
Bends down/leans low, keeps arms close to body, wears streamlined clothes.
3
(b)
Photocell and light source at either side of track to trigger an alarm when the light
beam is broken before the starting gun is fired.
2
Sufficient friction to prevent slipping, good water drainage/run off properties, not
too rigid/’gives’ a little to prevent damage to knee joints (any two).
2
Different events require footwear to keep friction low for speed, provide good ankle
support, have cushioned soles to reduce impact when jumping, for example.
2
(c)
(d)
(e)
(i)
2
Initial acceleration = velocity change/time = 12/2 = 6 m/s .
(ii) Air resistance increases as velocity increases, eventually air resistance force is
equal to the forward force, so there is no acceleration.
(f)
238
(i)
2
2
KE = ½ mv = ½ × 60 × 12 = 4320 J.
3
3
3
(ii) Power = energy transferred/time = 4320/2 = 2160 W.
3
(iii) Used to overcome resistance to motion, to maintain bodily functions, changed
to thermal energy to keep the body warm, used to produce sweat.
3
(iv) Wear warmer/cooler clothes to keep body temperature constant, streamline
clothes/position of body to minimise air resistance, reduce friction with track
(but not too much or runner will slip).
2

Forces and energy

Transcription

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