a PDF copy

Transcription

a PDF copy
MAKING MACHINES
out of paper and sticks
Tara Chklovski
an
publication
Published by:
IRIDESCENT
532 22nd Street
Los Angeles, CA 90007
Sponsored by:
Office of Naval Research (O.N.R.)
Written by:
Tara Chklovski
Edited by:
Ioana Urma
Book Design & Cover Illustration by:
IOANA/Ioana Urma
Cover is drawing of "How Things Work
Mural" based on Iridescent's educational topics, painted in Iridescent's 1st L.A.
Science Studio space (17'x20', 2010).
Photography by:
Anna Beatriz Galvao
Mariana Rutigliano
Linda Wong
Experiment models by:
Alay Bhayani
Jeffrey Cui
Shraddha Doshi
Gloria Hernandez
Juan Hernandez
Christopher Hong
Darryl Hwang
Denisa Lleshi
Dorina Lleshi
Matthew Miller
Nellie Querns
Elizabeth Windler
Technical advisors:
Tim Chklovski
Toby Cumberbatch
Sylvie Denuit
Matthew Loth
John McArthur
Kevin Miklasz
Thomas Stakelon
Sinchai Tsao
Pedagogical advisors:
Erika Allison
Vanessa Garza
Luz Rivas
Font is:
Avenir, by Adrian Frutiger, 1988
Copyright © Iridescent, 2011
All rights reserved
No part of this book may be reproduced or utilized in any form of by
any means, electronic or mechanical,
including photocopying, recording, or
by any information storage and retrieval
system, without permission in writing
from the publisher. Inquiries should
be addressed to: Iridescent, 532 22nd
Street, Los Angeles, CA 90007.
introduction
8
bird
boat
rube goldberg machine
make a…
10
12
30
hot air balloon
cool house
laser maze
eye bowl
heart
plumbing system
speaker
32
further reading
14
16
18
20
24
28
contents
4
introduction
Have you ever wondered how a gull’s wings work or how your heart is
able to pump blood up against gravity, how a hot air balloon is able
to lift hundreds of pounds just with hot air? These are just some of
the amazing things that you will learn about – by creating your very
own unique working versions.
To do so, you will need to keep a few things in mind.
•Creating something is very satisfying. There is no joy quite like that
of creating something new, beautiful, unique, something that is completely yours!
•But creating, building, designing, inventing and engineering takes
hard work. You must be willing to put in some effort into doing and
especially in learning and experimenting.
•You need to be courageous. Your model may fail the first time, the
second time, the third time. But it is OK! The Wright brothers studied birds, made observations, tested various designs that failed for
years and years before their first successful flight. So it is OK for your
model to fail many times. Just be brave, listen to what your model is
telling you and make changes each time you test it. It will work!
•Play around with the materials! Observe, notice how they interact
with one another, with your model, with the world. For instance, have
you taken two magnets and tried to push like poles together? How
far away do you start to feel the repulsion? What does it feel like
when the magnets are moved off-axis to each other? What about
moving one around the other in a circle? Try these things! That's how
you will learn! Only when you play with, observe and listen, will you
begin to understand how the world around you works. This is how
the great scientists and inventors worked. And you will be one if you
do the same!
Welcome and share in the pleasure of finding things out!
4
MAKING MACHINES out of paper and sticks
5
make a…
bird
GLIDE! Design + build
+ fly bird-shaped gliders. Observe which
designs fly the farthest.
In nature, birds with long, narrow wings - Sea Gulls, Albatrosses,
Swallows and Swifts - are very good gliders. They float in the air for
a long time without flapping. Can you think of some other birds with
long, narrow wings that are good gliders?
If you look from the side, you may notice that birds’ wings are curved.
This curved wing shape is called an airfoil. An airfoil changes the
direction of the flow of air: it pushes the flow down.
According to Newton's laws of motion, if air is pushed down by the
airfoil (the curved wing shape), then the airfoil will be pushed up by
the air, causing lift. The wings, and bird, lift up. This is the concept
of Action-Reaction: every force exerted has an equal and opposite
force exerted back. You can do a test of this by throwing a basketball
while standing on a skateboard. Did you move in the opposite direction from the ball (you should have!)? Your movement backwards is
caused by the force of the basketball pushing back on you.
Look also at the angle of the wing (from the side). Do you notice a
difference when the wing is angled more steeply? The more steeply
the wing is angled, the more lift will be generated, and the bird will
go up higher.
collect
POSTER BOARD OR STIFF SHEET OF PAPER (1 SHEET)
NOSE WEIGHT (PAPER CLIPS OR PLAY-DOH)
TAPE
SCISSORS
RULER
experiment
1. Observe different birds in nature or by looking at videos.
2. Draw the different wing shapes of the birds you see glide far.
3. Invent a wing shape design of your own by first sketching it out
on a piece of paper. This will help you plan out the design shape
carefully, because once you cut it out, it will be hard to join the
pieces back together!
8
MAKING MACHINES out of paper and sticks
4. Build the body of your bird. Try and choose a shape that will be
strong and can survive many crashes.
5. Cut out the horizontal and vertical part of the tail.
6. Draw and cut out the wings. Cut a variety of wing shapes to try.
7. Tape the parts together, making sure the wings and tail are
taped evenly on the body.
8. Put a little play-doh or a few paper clips in the nose, as a weight.
9. Throw the plane gently and see how it flies. If it goes up or dives
too steeply, it is not balanced. What do you think you can do to
balance it better? Try it with the different wings and wing angles.
What angle works best on your bird? Why do you think this
reflect
angle works best? What wing shape helps your bird go farthest? What are you proud of observing from nature?
9
boat
LEARNING FROM
BIRDS: design + build +
sail a sailboat. Observe
which direction the sail
needs to be pointed in
so that the boat can go
forward.
Have you ever wondered how sails help a boat to move forward?
You may have noticed that the sails of sailboats - pushed by the wind
or flow of air - are curved (in cross-section or when looking at them
from the side, bottom or top). This curved shape is called an airfoil
(just like on a bird’s wing - see bird project p. 10). In the sailboat, the
airfoil changes the direction of the flow of air, pushing the air back in
a certain direction. You can think of it as a kind of reflector for the air.
The air hits the sail or airfoil and bounces back off of it. The direction the air is pushed off of it depends on the angle of the sail to the
incoming wind or airflow.
When the sail or airflow push the incoming flow of air or wind back,
the boat is pushed forward. The boat is pushed forward exactly in
the opposite direction to the direction that the wind is pushed back.
This is because, as Newton's laws of motion state, for every force that
the sail exerts on the air, there must be an equal and opposite force
from the air on the sail. This is the concept of Action-Reaction.
collect
PLASTIC BOTTLE
WOOD SKEWER
CONSTRUCTION PAPER
ALUMINUM FOIL
WIRE
TAPE
SCISSORS
RULER
LARGE BOX FAN
LARGE OPEN CONTAINER OF WATER
experiment
1. Draw out your sailboat design on a piece of paper before start-
ing. This will help you plan out the design carefully, because
once you cut the bottle, it will be hard to join the pieces back
together!
2. Based on your sketches, build the body of the boat out of the
10
MAKING MACHINES out of paper and sticks
plastic bottle pieces (ask an adult for help cutting the bottle,
making sure edges aren't sharp or pointy).
3. Attach the skewer to the boat base.
4. Shape the aluminum foil into a curved sail form around the skew-
er. Design the sail so that it doesn’t get crushed (as aluminum foil
can get crushed very easily). Try and put in some support braces
using posterboard or wire.
5. Test the sailboat in the water and see which direction the boat
goes depending on how you direct the fan and how you angle
the sail.
What sail angle helps the boat sail the farthest? Why do you
reflect
think this angle works best? What sail shape helps your boat
go farthest? What aspect of your boat are you most proud of
designing?
11
rube goldberg machine
ENERGY TRANSFER!
Design + build + set in
motion a Rube Goldberg machine.
Rube Goldberg machines are contraptions that perform simple tasks
in unique, fun, and indirect ways. Some Rube Goldberg machines
use a complicated series of actions to simply move an object from
one place to another.
Any object that is moving, has what is called kinetic energy; giving
an object more speed means giving it more kinetic energy. Kinetic
energy can be transferred from one object to another by a collision,
like when one domino tips over into another domino. Even without a
collision objects can gain kinetic energy if they fall down or roll down
a ramp. The goal of a Rube Goldberg machine is to find creative
ways of making this type of energy transfer happen using a variety of
simple machines (see experiment) attached together in the form of a
complex machine.
collect
experiment
ANYTHING THAT YOU CAN FIND AROUND THE HOUSE!
Try and make YOUR OWN UNIQUE Rube Goldberg that has each of
the six simple machines listed below and can transfer energy in at
least five different ways:
PULLEY: A simple machine that uses grooved wheels and a rope to
raise, lower or move a load.
LEVER: A stiff bar that rests on a support (called a fulcrum) which lifts
or moves loads.
WEDGE: An object with at least one slanting side ending in a sharp
edge, which moves material apart.
WHEEL & AXLE: A wheel an axle lifts or moves loads.
INCLINED PLANE: A slanting surface connecting a lower level to a
higher level.
SCREW: An inclined plane wrapped around a pole which holds
things together or lifts materials.
1. Decide on the task that you want the Rube Goldberg machine to
do. For example, to move a ball into a box or to open a door.
12
MAKING MACHINES out of paper and sticks
2. Think of ways you can make your materials interact with each
other. How can one energy transfer start a chain of actions?
Test each energy transfer before putting the entire contraption
together. Make sure you think about five different energy transfers that you will implement.
3. Once all the testing is done, put your Rube Goldberg together
and watch it perform the task you chose to do in a very complicated, but fun way. If the Rube Goldberg stops midway, retest
and redesign that failed energy transfer.
How many different energy transfers did your Rube Goldberg
reflect
have? What are some energy transfers that you observe in
your room, outside your window, in the playground? How
can you modify your Rube Goldberg machine to use wind to
transfer energy? How about water? How about solar energy?
13
hot air balloon
HOT AIR! Design +
build + fly a hot-air
balloon to lift a weight.
The better designed
the balloon is, the
more weight it will be
able to lift.
Why do hot air balloons rise up? Hot air balloons rise because they
are filled with air hotter than the air around them, and hot air is lighter than cold air. Why is hot air lighter than cold air? When a material
is heated, its molecules absorb the heat or energy and with this extra
energy are able to move around at greater speeds.
In objects that can stretch and expand, molecules with extra energy
can move farther apart. When the molecules move, the object grows
in size or volume. It doesn't change in weight, though, because the
number of molecules doesn't change. It is made of the same number
of molecules, just located farther apart. This makes the object less
dense, but maintains its weight.
When we start heating the air of a hot air balloon, the air molecules
start moving around with more energy. As the hotter air expands,
the balloon expands, but its weight does not change right away.
Once the balloon has expanded as far as it can, then the energetic
molecules start escaping out of the hole at the bottom. This leaves
less molecules inside, making the balloon lighter than the cooler air
around it. The balloon rises.
collect
POSTER BOARD (1 SHEET)
TISSUE PAPER (10-12 SHEETS)
GLUE STICK
SCISSORS
RULER
PIECE OF WIRE TO SHAPE INTO A RING
STRING
HAIR DRYER
experiment
1. Draw and cut a template for the hot air balloon side panels out of
the poster board. You will use this to make tissue paper cutouts
of the same size. Draw the typical shape you see in modern balloons or try creating new shapes you would like to test.
2. Using your template, cut 8 tissue paper side panels.
14
MAKING MACHINES out of paper and sticks
3. Glue the panels together into a balloon shape.
4. Cut out a circular piece of tissue paper to cover the top of the
hot air balloon and glue it on.
5. Cut some wire coil and shape into a circle.
6. Place the coil at the bottom of the balloon, fold over the tissue
paper over it, covering it, and glue it in place.
7. Make a basket out of the poster board and attach it with string or
tape to this coil ring, and place a weight in the basket.
8. Heat up the balloon with the hair dryer, let it go and watch it rise!
How do you think the size of the balloon affects how much
reflect
weight is in the basket? Why do you think size makes a difference? Does shape make a difference? Look at early balloon
designs. Try them out and see if a particular shape is better
at carrying more weight. What are you proud of learning?
15
cool house
CONVECTION! Design
+ build a house with
doors and windows
carefully positioned to
help remove the hot air
and cool the house passively (without using
a fans or the AC). The
goal is to save energy.
If you have an attic space or have ever been in an attic space on
warm days, have you noticed how much warmer it is in there than
in the rest of the house? How about in the basement? In the days
before refrigerators, basements - because they are much cooler were used to store food items. Next time it's hot inside, try lying
down on the floor and see how you feel. It's cooler than when standing up, isn't it?
Warm air rises to the top because it is lighter, or less dense, than
cold air. Air molecules with more heat, or energy, move around at
greater speeds and end up farther apart. So in the same amount of
space (volume), warmer air will have less molecules in it than colder
air. This makes it less dense or lighter, and it makes it rise up.
As warm air rises and cold air sinks, a directional movement of air is
created which is called a convection current.
Have you ever wondered why on a warm day it is warmer inside a
parked car than outside? This concentration of heat inside the car
is caused by the greenhouse effect. A greenhouse is an enclosure
made of glass or other transparent materials - typically for plants that allows sunlight in, but then traps some of the sunlight's energy
inside. This trapped energy is heat. A car parked in the sun heats up
for the same reason, heat energy from the sunlight gets trapped.
collect
CONSTRUCTION PAPER
TAPE
SCISSORS
TWO INCENSE STICKS & HOLDER
CAUTION: only conduct
this experiment under
adult supervision.
experiment
ONE MATCHBOX
THERMOMETER
1. Knowing that warm air rises and cold air sinks, can you think
about which parts of your house are the hottest? Sketch and
design the location of your openings (doors and windows) so that
16
MAKING MACHINES out of paper and sticks
the heated air will come out and the cool outside air will come in.
2. Build your cool house out of construction paper.
3. Once the house is complete, put a lit smoking incense stick
inside the house in an incense stick holder. BE CAREFUL NOT TO
TOUCH THE PAPER WITH THE INCENSE STICK AND SET IT ON
FIRE! If the placement of windows and doors is well designed for
cooling with natural ventilation, then the smoke will come out.
4. Place a thermometer at various points inside the house. Where
do you get the highest reading?
What design worked best? What placement of openings
reflect
helped more smoke to get out of the house? Where did you
get the highest temperature reading? Why do you think this
is? Can you think of some other examples of convection you
can see around the house?
17
laser maze
Design a laser maze
that reflects the laser
beam through as many
obstacles as possible.
When light waves hit a material, they cause the atoms (specifically,
the electrons in metals) to oscillate (move back and forth). These
oscillations cause the atoms to radiate a small wave back out in all
directions. The reflected waves of many atoms combine to form a visible reflection.
In the case of metals, the electrons in the atom's outer shell (farthest
from the central nucleus) are not attached to the atom; they are free
to move throughout the metal with very little resistance. When light
shines on metal, it makes these free electrons oscillate or vibrate and
the energy reflected is visible light.
A mirror is mostly made of glass, but it also has a thin metallic film
on the back side. It is that metallic film that reflects the light passing
through the glass. The glass is only there to hold up the very thin film.
A few ideas, tips and terms to be aware of:
∙∙ Light paths are only visible when there are particles in the intervening medium (such as smoke or fog or dust particles in the air).
∙∙ Moving a mirror back doesn’t increase the amount viewed in it.
∙∙ Incidence angle = angle at which light hits a surface.
∙∙ Reflection angle = angle at which light is reflected off a surface.
collect
FOG MACHINE & FOG JUICE (FROM A PARTY SUPPLY STORE)
LASER POINTER (KEY CHAIN OR BIGGER IF POSSIBLE)
MIRRORS
CONSTRUCTION PAPER
TAPE
POPSICLE STICKS
SCISSORS
experiment
CAUTION: only conduct
this experiment under
adult supervision.
18
1. Cut a pattern of holes in the construction paper. Your obstacle
course will be more challenging if the holes are very small.
2. Glue popsicle sticks along the side of the paper so that the
obstacle course can stand upright. Stand them up in play-doh.
MAKING MACHINES out of paper and sticks
3. Use play-doh to make the mirrors stand upright.
4. Turn on the fog machine and point it towards the obstacle course.
5. Turn on your laser pointer and reflect the beam off of as many
mirrors as possible so that the beam can go through the obstacle
course holes, from one end of the maze to the other.
Do you see a red path of light when you shine the laser point-
reflect
er onto a mirror or something else? Is it what you expected?
What happens when you add fog? Do you see the light path?
What do you think is happening? Where is the image you see
in the mirror? Can you illustrate your thoughts on how it is
formed? What happens when you move the mirror back? Do
you see more of yourself or of an object? Can you draw and
explain how the light travels in your obstacle course?
19
eye bowl
REFRACTION! Build an
eye model and see how
its lens bends light to
reproduce an image.
Light waves travel at different speeds through different mediums
(materials). As light crosses from one medium into another, the same
wave will change the speed at which it is traveling. This happens, as
you probably guessed, because the two mediums interact with the
light in different ways.
The way that light travels through a materials is by passing on energy.
As a light wave enters a material, it hits and gets absorbed by the
electron of an atom in that material. The electron doesn't keep the
energy for long though, and soon it re-emits the light wave.
This process continues from atom to atom, where each atom is like
a baseball player catching the light wave and then throwing it to the
next atom. The atoms of different materials take different amounts
of time to catch and throw the light waves, making light travel more
slowly when it enters a material. In a vacuum (an empty medium
without atoms) light travels at a speed of 299,792,458 meters per second or about 186,282 miles per second. Through a material, it takes
longer.
Imagine sitting on a boat and looking out at a fish in a lake. For your
eye to see the fish, there must be light traveling from the fish to your
eye. This light wave travels slowly through the water and then when
it enters the air it speeds back up. The path of the light wave makes
an angle with the boundary between the water and the air. At this
boundary the path of the light bends.
To understand why light bends, lets use an analogy. Imagine you are
pushing a stray shopping cart (lightwave) from the grass (water) onto
a parking lot (air). If you go straight from the grass into the parking
lot the cart will speed up after crossing the boundary. What if you
approach the boundary at an angle, so that the front right tire hits
the pavement first? What happens?
The front right wheel will begin moving faster than the other wheels
and this will cause the cart to start to turn to the left. Once you leave
the grass you will be pointed in a new direction. Going over the
20
MAKING MACHINES out of paper and sticks
boundary bent your path, just like the light wave's path became bent,
all because the wave moves at different speeds in different materials.
This is called refraction.
Understanding refraction can help you better understand how the
eye works. The lens in your eye (the front curved part of the eyeball)
bends the light waves which enters it. The light waves are bent so
they come together or “focus” at a particular distance back from the
lens, called the focal distance.
The lens in your eye works the same as other lenses (camera, telescope, microscope): it bends the light waves, changing their direction of travel. Lenses can do this because they are made of a different material than the mediums or materials around them. Light
passing through the air is bent by a glass lens.
If an object is placed in front of a lens, some of the light that bounces
21
off the object will pass into the lens. This bounced light is refracted
through the lens, and becomes focused into an “image.” Think about
a camera. If you put an object in front of the camera, light bounces
off the object and passes through the lens where it is refracted. The
lens uses refraction to focus the light to form an image. On a digital
camera, that image is what is displayed on the back screen.
Pick up one of the magnifying lenses, hold it away from you and look
at your friends through it. How can you tell that the light passing
through the lens is changing direction?
collect
TWO CLEAR PLASTIC BOWLS (THAT YOU CAN SEE THROUGH
CLEARLY, WITHOUT DISTORTION)
A SHEET OF WAXED PAPER OR TRACING PAPER
CLEAR PACKAGING TAPE (OR MASKING TAPE)
SCISSORS
A LENS OR MAGNIFYING GLASS
experiment
1. Put the bowls together, rim to rim (opening to opening).
2. Tape them together. It should look sort of like a flattened ball
when you are done. This model represents the eye-ball.
3. Cut a circle out of the waxed paper or tracing paper. The cut-out
paper should cover the bottom of one of the bowls.
4. Now tape it to the bottom of one of the bowls. The paper will act
as a screen for the image to form.
5. Tape the lens to the bottom of the bowl on the side opposite the
paper.
6. Place your eye model between the object you want to look at
and your own eye. Adjust the distance between the model and
your eye until a clear image is formed on the screen. Look at the
paper. Do you see an image on the paper? What is the shape of
the image?
7. Is it upside down? What is its color?
8. Point the eye model in a slightly different direction and observe
what happens to the image. What do you see if you point the
lens of your eye model at your friends or parents?
22
MAKING MACHINES out of paper and sticks
9. Describe the image you see.
What was the hardest part of building the model? Can you
reflect
use the eye model to show your friends or parents how an
eye works? What was the best part of this experiment?
23
heart
CIRCULATION IN
YOUR HEART! Design
+ build + operate an
artificial heart.
Your heart pumps and circulates blood to every part of your body so
that all of your cells get the oxygen and nutrients they need to survive. In a single day, your heart can pump about 1,000-2,500 gallons
of blood. To keep you alive, your heart works without any breaks or
rests! But, unfortunately, the heart is not indestructible. People can
suffer from the break down or weakening of the heart, or they can be
born with a weaker heart. This can result in heart failure, where the
heart can no longer pump enough blood for the body's needs.
In the most severe cases of heart failure, the only long term solution is to replace the heart. For many years the only way to replace
a heart was through a transplant, where a failing heart is replaced
with a living heart from an organ donor. Since this process was, for
many reasons, very difficult, more recently, doctors, scientists, and
engineers have come up with another transplant option: an artificial
heart!
Making an artificial heart was very hard because it was trying to take
the place of something very complex. There are four chambers in
your heart, and each one has a specific job to do to make sure your
body has enough oxygen. Blood comes into the right atrium from
the body. This blood is low in oxygen and high in carbon dioxide.
Blood is then pumped into the right ventricle and the next stop is the
lungs to drop off the carbon dioxide and pick up more oxygen. From
the lungs the blood is pumped back to the left atrium and then on to
the left ventricle which finally pumps the blood back into your body.
An artificial heart has to be designed to do the job of each original
chamber correctly. That's tough to do! On top of that, an artificial
heart needs a new power source. A real human heart is made of
muscle, and just like the muscles in your arms and legs, the heart
depends on the food you eat to give it the energy it needs to pump
blood, but an artificially heart can't use the food you eat.
There are several artificial hearts that exist, but they too have some
issues such as size, weight, and attachments.
24
MAKING MACHINES out of paper and sticks
JARVIK 7 was the first artificial heart used in people 1982. This heart
has only two pumps which replace the two lower chambers of a
person's heart that has stopped working. The power system for this
heart is large and bulky and it connects to the pumps through tubes
that poke through the skin – ouch!
ABIOCOR, a more recent version, has a mechanical pump which
completely replaces the pumping action of the lower chambers of
a person's heart. It allows doctors to completely remove a person’s
heart and replace it with a whole new system. The difficulty with this
model is that a lot of equipment has to be placed inside the body.
The equipment is bulky and puts a lot of pressure on the other
organs.
25
collect
PLASTIC TUBING
FOUR SMALL PLASTIC BOTTLES
FOOD COLORING
THICK STRAWS
THIN STRAWS
SCISSORS
TAPE
BALLOONS
experiment
1. Draw a diagram of the four chambers of the heart and how they
connect to each other to use as an organizational guide. You will
use the plastic bottles to represent these chambers.
2. Take the four bottles and make holes in each of the caps, big
enough to fit the tubing.
3. Tape two bottles together with the cap sides touching. Do the
same with the two remaining bottles.
4. Take a sharp pencil or scissors and make a hole at the bottom of
the first two bottles that represent the upper chambers of the
heart and two holes on the top of the bottles that will represent
the lower chambers of the heart.
5. Use the clear tubing to connect the top bottles to the bottom
bottles through the holes made. The bottom bottle should have
the rubber tubing touching the bottom of the lower bottle so
that when the bottom bottle is squeezed water will flow up the
tube and pour water into the top bottle.
6. Remember to put valves in the caps of the bottom bottle so that
no water is leaking back up to the top bottle when the bottom
is squeezed. Do this for the other side two in order to complete
your four chambered heart.
reflect
What can you change about your four chambered heart to
make it pump better? What would happen if you only had a
three chambered heart? Where would the blood from the top
chamber go? Why does the heart need a left and right side?
26
MAKING MACHINES out of paper and sticks
paste
your
heart
diagram
here
27
plumbing system
Design a plumbing
system which can
distribute water to five
“cells” in your body in
under 30 seconds!
Your circulatory system controls the movement of blood through
your heart and throughout your whole body. The blood circulates
(moves) in a continuous, closed loop. The movement is generated
(started) by the pumping action of the heart.
Your house also has a circulatory system, but instead of blood, it
pushes water around. It is called the plumbing system and it is composed of pumps, pipes, and valves.
Both your body and your house have circulatory systems that operate using the same parts and concepts:
∙∙ A pump: the heart (body); a mechanical pump (house).
∙∙ Distribution vessels: arteries and veins (body); pipes (house).
∙∙ Control valves: valves in the heart (body); faucets and the toilet
lever (house).
∙∙ They transport both nutrition and waste: blood transports oxygen
and nutrients and removes cell waste (body); the plumbing system
carries both fresh and waste water (house).
One of the most important tasks of the circulatory system is to
deliver nutrition and remove waste through blood - to and from the
cells - at incredibly high speed. The size of your blood vessels controls the speed of blood flow: in large vessels the flow is slow, while
in small vessels it speeds up. This is because the same amount of
blood needs to move through under the same pressure (put out by
the pump of your heart). If the opening is smaller, the pressure will be
greater and it will be pushed through faster.
collect
PLASTIC TUBING
THICK STRAWS
THIN STRAWS
SCISSORS
TAPE
FIVE CUPS
BALLOONS
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MAKING MACHINES out of paper and sticks
1. Sketch ideas for your design, figuring out how the system will
experiment
work to fill up all the cells at the same time. This is necessary.
2. Use the materials listed to construct your plumbing system.
3. Check to see whether or not you have any leaks in your pipes.
Also check to see if you need to add any valves to control the
flow of “blood.”
4. Pour water into the entry part of your plumbing system and
watch how it flows!
What could you change about your plumbing system in order
reflect
for the ”blood” to flow to the cells more quickly? How about
more slowly? How does the size of your pipes affect the
speed of blood flow?
29
speaker
USING PRESSURE
WAVES TO CREATE
MUSIC! Design + build
a speaker that will use
electricity and magnets
to put pressure on the
air and create sound
waves (musical sounds).
Have you wondered how you are able to hear a sound that was emitted really far away? Most times you can't feel or see anything. Sometimes though, if the sound is loud, you can even feel vibrations!
Sound can be thought of as waves of pressure that move longitudinally (in the directional line of the sound without going up and
down). Sound can move through all kinds of mediums: air, water or
even hard materials like wood.
The medium or material the sound moves through is made up of
tiny molecules. When these molecules are made to vibrate by some
force, they transfer or pass the vibrations on to the molecules next
to them. This continuous transfer results in a sound wave, a wave of
transferred vibrations.
You can create a sound with your vocal chords, but also by moving
something with your hands, such as waving a fan through the air. Try
it. Do you hear something? Those are molecules of air passing the
energy you threw at them on as vibrations in the form of a sound
wave. You put pressure on the air and made it vibrate!
collect
NEODYMIUM MAGNET
WIRE 32 OR 34 AWG (AMERICAN WIRE GAUGE)
PLASTIC CUP
ALLIGATOR CLIPS
SANDPAPER
TAPE
GLUE
SCISSORS
PENCIL
HEADPHONES
experiment
1. Leaving a 10 centimeter tail of the wire free at the beginning and
at the end, wrap the wire around a rolled up piece of construction paper about 50 times.
30
MAKING MACHINES out of paper and sticks
2. Use sandpaper to rub the insulation off the ends of the tails.
3. Tape the magnet against the outside, bottom, of a plastic cup.
4. Cut the speakers off of the headphones and strip away the plas-
tic insulation to expose all four wires. Sand away any insulating
coatings on these wires.
5. Plug in the headphone jack and turn on the sound for the device
you are using.
6. Connect some of the exposed wires from the headphones to
the free tails of the coiled wire. Test your choice by holding the
rolled-up paper up and down with the coiled wire by the magnet.
Experiment with the connection until you hear the right sounds.
How can you change your design to increase the volume
reflect
of your speaker? What can you do if the sound quality isn’t
good? How does the size of the cup affect the sound?
31
further reading
EASY
The Great International Paper Airplane Book by George Dippel,
Howard Gossage and Jerry Mander, 1971.
Body. Make It Work! by Andrew Haslam, 2000.
Flight. Make It Work! by Andrew Haslam, 2000.
Insects. Make It Work! by Andrew Haslam, 2000.
Photography. Make It Work! by Andrew Haslam, 2000.
Sound. Make It Work! by Andrew Haslam, 2000.
Everyday Machines: Amazing Devices We Take for Granted by
John Kelly, with David Burnie and Obin, 1995.
The Robot Zoo: A Mechanical Guide to the Way Animals Work
by John Kelly, Dr. Philip Whitfield and Obin, 1994.
The New Way Things Work by David Macaulay, with Neil Ardley,
1998.
The Amazing Book of Paper Boats: 18 Boats to Fold and Float
by Melcher Media (creator), with Willy Bullock (illustrator) and
Jerry Roberts (text author), 2001.
Illustrated Guide to Aerodynamics by Hubert Smith, 1991.
700 Science Experiments for Everyone compiled by UNESCO,
1964.
32
MAKING MACHINES out of paper and sticks
Amateur Naturalist: A Practical Guide to the Natural World by
ADVANCED
Gerald Durrell with Lee Durrell, 1993.
Why Things Break: Understanding the World By the Way It
Comes Apart by Mark Eberhart, 2004.
The Seven Secrets of How to Think Like a Rocket Scientist by
James Longuski, 2006.
How to Design a Boat by John Teale, 2003.
The Simple Science of Flight by Henk Tennekes, 1996.
Physics, Fun, and Beyond: Electrifying Projects and Inventions
from Recycled and Low-Cost Materials by Eduardo de
Campos Valadares, 2005.
The Flying Circus of Physics by Jearl Walker, 2006.
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