How to write a good scientific or laboratory report

How to write a good scientific or laboratory report
(Student ID Number)
Your Name (Hywel Owen)
School of Physics and Astronomy
The University of Manchester
A Scientific or Technical Report
February 2014
This work was (perhaps) performed in collaboration with (Student ID
Number/Name).
Abstract
In this report template we give some notes on how to write a good lab report.
We observe that a good report and a good paper have similar aims and content, and
that the abstract should be short and to the point. We find that good reports are
typically less than twenty pages long, and that a lot of text can be cut whilst still
conveying information well. Clear, simple text is better than superfluous verbosity.
1. Introduction and Use of Software
This document serves several purposes.
a) It uses the same template that defines the house style in the School of Physics and
Astronomy at the University of Manchester. Therefore you can edit it to produce your
reports.
b) It contains examples on the use of Microsoft Wor.
c) It contains instructions, advice and guidance on writing lab reports.
You are encouraged to use this template for your reports you are advised to read
it carefully. You can write your report by editing a copy of this document. It’s a good
idea to keep an unchanged copy for reference, (make it read-only and, for example,
call it “original”). Do not change the style, i.e. the fonts, spacing, layout etc. Of course
you should make sure you delete all the original text of this document when you
finish!
You will see in the section heading that you can change the heading titles
according to what you want to say. You can also change this template, or even use
other software such as LaTeX to prepare your reports. The most important goal in
writing is that the report is readable; the headings should be clear to see by the reader
and they should be and consistently formatted. For example, particularly important
points can be highlighted in italics to make them stand out, but you shouldn’t overdo
this. Underling is sometimes also used, but doesn’t usually look as good. Bold text is
often used to denote named things, for example to denote programming languages
such as Matlab or Python.
The reader wants to be able to glance through the report and easily find their
way around; you can see that judicious use of paragraph breaks and white space
between them help the reader to structure their reading. Through this report we will
repeatedly point out how important it is to not make the reader fight for information.
For example, there is no particular reason why you can’t repeat information, for
example in both figure captions and in the main text; but- and this is important - don’t
repeat yourself unnecessarily.
It is often said that a good report – or for that matter, a good presentation – has
the following structure:
• Say what you’re going to say
• Say it
• Say what you said
This advice is terrible. A better way to think of a report is to try to achieve the
following:
• Introduce the purpose of the work
• Describe the work in detail
• Explain the significance of the work
2. Some Comments on Style and Layout
Different organisations and their publications demand particular ways of doing
things when writing reports or papers, and often demand a particular style (sometimes
called a ‘look and feel’) for their reports; a template may be provided, and for
example several templates are provided in our own School. On occasion these
templates will either not look very good, or be a bit hard to work with. That’s just
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tough; sometimes you don’t get a choice how things look. But you can try to work
within the rules.
On the other hand templates do offer something that is useful but often not
explained properly, and that is the provision of Styles. If you look in the toolbar of this
report while editing it, you will see buttons that allow you to format parts of the text
so they become - for example - body text (the technical term for the main text, for
example the text of this paragraph), or to format headings, figures, and so on. Use
them. Use the Style buttons, they will make your life much, much easier.
3. How to Write Sentences Clearly
Scientific writing is much like any other form of writing in that you are trying to
convey information correctly, clearly, and convincingly; these are the three ‘C’s, at
least according to me. However, scientific articles differ from, say, a newspaper
article in that statements should be made rigorously; that means you should be
unambiguous (you should use accurate language), and that you should justify all
statements and assertions. The result will be something approaching a scientific style.
Good scientific writing will not jump fully-formed from your typing hands
without practice, in the same way that good public speaking is only a natural talent for
the very few. But both can be practised, and the feedback you get on your reports and
your speaking will help you get better. You should get used to having your text
commented upon ruthlessly: this doesn’t change in later life. Developing as a speaker
should go hand-in-hand with developing as a writer.
To achieve clarity, first and foremost you must avoid spelling mistakes; nobody
likes to read poorrly-checked text; turn on your spell checker and pay attention to
spilling mistakes, realising that not all spilling mistakes will be picked up by your
word-processing software. By the way, nobody should really care about spelling
differences such as color or colour and whether one is French and the other is
American; the important thing is that you are consistent, and only use one spelling
choice for a word in any report. However, if you make daft mistakes like calling it
Avocado’s Number you deserve everything you get; your spell checker can be an
enemy as well as a friend, so be careful.
Next, make sure that every sentence you write is actually a sentence; surprising
how often people miss this point (hint: that last clause was incorrect, as the text in
these parentheses). Or like this sentence, which isn’t a proper sentence. This point
also applies for different parts of a discussion joined by colons and semicolons. There
is a difference in how they are used, and you should note that they were over-used in
the text you just read. Finally, commas are invaluable in helping break up a sentence,
but make sure you don’t over-use them, particularly in long sentences, or you may
find the reader loses their way through such a long sentence, or perhaps you lose your
way, and then nobody really knows what the point of it was, particularly once the
sentence approaches lengths of a hundred words or more. Another thing to pay close
attention to is to make sure that when you use the word ‘this’, the reader can figure
out what ‘this’ refers to; just because you know your train of thought, don’t assume
the reader does. Sometimes a different pair of eyes from your own can help.
Punctuation and the other aspects of technical writing are described well in a
number of books and other guides, and some good guides may be found on the
Internet. A particularly prominent one is the Chicago Manual of Style, which contains
much good advice. However, the manual is quite long, so a few good tips are repeated
here.
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Hyphenation can initially be tricky but is actually quite easy. You can call it a
‘spell checker’, or a ‘spell-checking system’; to make the latter term properly correct
the first two words are hyphenated, but in this case you can get away with it and just
write ‘spell checking system’. Sometimes you can’t though because omitting the
hyphen changes the meaning: the trick is to read out the words with differing
emphasis to see how they might be ambiguous. Similarly, placement of commas can
make a big difference. A panda that eats shoots and leaves is quite different from a
panda that eats, shoots, and leaves. On that note, make sure you get your use of
aprostophes correct. ‘Knowing your shit’ is really very different to ‘knowing you’re
shit’. Remember that the plural of ‘apostrophe’ is ‘apostrophes’, not ‘apostrophe’s’,
and that sometimes single quotation marks (‘) can be mistaken for apostrophes and it
might be better to use double quotation marks (“).
Stating numbers is most properly done as follows: numbers less than a hundred
are given in word form, for example there are seven colors in the rainbow, it’s a
twenty-one gun salute, and there are a hundred ways to leave your lover; but there are
101 Dalmatians. Whilst this is the proper way to write numbers, usually no-one will
care if you say for example that there are 49 varieties of Heinz baked beans rather
than forty-nine varities. However, people do get more upset if you get your
capitalisation wrong. If we buy someone a gold ring the word ‘gold’ is not capitalised,
and neither is silver, nor aluminium, carbon or any other element. But when they are
abbreviated they are capitalised, for example one should use ‘Au’, ‘Ag’, ‘Al’ and so
on. Isotopes may be denoted in a variety of ways: 12C, C-12, or carbon-12. If you
look closely at the previous two sentences you will see that one of them used an
‘Oxford comma’ and the other one did not; it doesn’t matter if you use an Oxford
comma or not, as long as it doesn’t change the meaning of the terms. Returning to the
point about referring to chemical elements: it doesn’t matter which of the notations
you use as long as you do it consistently. It’s just distracting to talk about carbon-12
and its relationship to 13C, so talk instead about carbon-12 and carbon-13. It’s just
like talking about seven brides for 7 brothers: it’s annoying.
3. How to Convey Concepts Clearly
Remember, the basic aim of the report is to communicate your results to a
literate – that is to say, a scientifically literate – reader, and to convince that reader
(who may often by skeptical) that she or her should believe your results. Of course
this includes your claimed accuracy. Your result may be a numerical value (for
instance the acceleration due to gravity) or it may be the confirmation that some
physical phenomenon is observed (for instance the form of the diffraction pattern
produced when light passes through a slit). Also remember that the key to good
communication is to keep things simple; write short sentences and, where there is a
choice, use simple words everyone understands rather than long ones that you hope
might impress the reader (or marker). 1500 words of text in a report is usually enough
to say what you want to.
4. Structure of a Lab Report and Headings
Whilst this depends a bit on the particular template and house style, nearly all
scientific reports have the following elements:
• Title/authorship;
• Abstract;
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• Content;
• Acknowledgements (you will rarely have these at undergraduate stage);
• References.
(note how lists are correctly separated using semicolons, but usually no-one notices if
you don’t use them)
Your reports will be like this, and the main body of the text (the ‘Content’ part
above) should be sub-divided into sections with appropriate headings, and possibly
also occasionally sub-sections and sub-headings. The type of content that is usually
included may include the following:
• Introduction;
• Theory (sometimes this is part of the introduction, or it can appear
elsewhere);
• Equipment (if appropriate);
• Measurements (or simulations);
• Results;
• Discussion.
But, it is very important to understand that this is not a prescription that you
must always have exactly the headings given here: Rather, if you are writing a report
there should be a discussion of the theory, a discussion of the equipment, some
measurements, and so on. Usually – as in the case of the present report – the headings
will differ. For example, an experiment on Thermal Diffusivity might have the
following headings: Theory of Thermal Diffusivity, Temperature Measurements,
Method of Construction, Comparison of Methods, The Method of Exact Fractions,
and so on.
Another very important thing to note is that you don’t have to artificially divide
up your content into the sections: you just have to make sure those parts are in the text
somewhere, and in a logical order which usually reflects the ordering described
above. It’s much more important that the text makes a clear logical argument from
beginning to end. This takes practice, and you may find yourself writing a few reports
before you get the hang of it. But to help you get better, here are a just a few tips:
• Equipment and named terms should be introduced before using them: the
reader does not have access to your lab script, for example;
• You can often leave the finer details of theory to a suitable reference, but
should give the gist of how something works;
• All assertions should be justified, ideally by the results of your work;
• Your work is not carried out in isolation; how do your results compare with
other peoples’?
5. What Goes on a Title Page?
The layout of the Title Page is fixed by the house style. It consists of the Title,
Author(s), Institution, Function, Date, (partner, if appropriate) and the Abstract. The
spacing and font sizes are specified by the first page of this template.
5.1. The Title
This should be short and informative. Capitalise the first letter of the first word.
Avoid abbreviations and jargon.
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5.2. About Abstracts
Every report or paper must have an abstract (there are things called ‘Letters’ in
the scientific world that do not have these, but these are rare and actually they
incorporate an abstract of sorts as well). An abstract should be about 50 to 250 words
long. It should clearly, concisely and precisely state what the report is about, the
experimental technique used, the final results and the claimed accuracy. Give a single
result for any measured quantity so that it can be quoted. Don’t give references in the
abstract and avoid equations as far as is sensible. Avoid using symbols, so that you
don’t waste space defining them. Don’t use tables or graphics.
The abstract has to stand alone. The idea is that someone can read it, and then
decide whether or not to read the report itself. The next section is an example of a
good abstract.
Above all, remember that physics is a numerical discipline, so if you have made
a measurement (an example might be measuring the mass of the electron) you should
be putting the numerical value in the abstract. It is surprising how often the actual
results are not put in the abstract; they should be.
5.3. Example of a Good Abstract
The acceleration due to gravity (at Manchester) was determined using a Kater’s
pendulum, which is a rigid pendulum with two parallel knife edges that define the
axes of rotation and its length. The acceleration due to gravity was determined to be
9.814 ± 0.002 m s 2. The accuracy is limited by the measurement of the length of the
pendulum.
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6. Scientific Style
Scientific papers are written in a particular style. This is characterised by careful
clarity, wording that is both concise and precise and by the complete absence of
verbiage (otherwise known as waffle). Scientists are by nature cautious – they
shouldn’t make unwarranted claims. A scientific paper has to stand on its content and
scientific merit and the approach is the antithesis of the hype, spin and attention
seeking that are typical of the media and advertising.
It is usually best to use short sentences as this aids clarity. Use the past tense to
describe what you did and use the present tense to describe ongoing situations (such
as theory). Avoid the future tense, unless you really mean it. Make use of both the
passive voice (e.g. measurements were made …) and the active voice (we concluded
…). Both are fine and you can use them as needed.
The emphasis in a report is on the scientific result and not the particular
individuals, so avoid excessive use of “I” or “we”. The occasional “we” is acceptable.
This document itself contains very few of either.
As we said above, every part of the text must be written in grammaticallycorrect English sentences and there should be no spelling mistakes. There now follow
some particular points, which are based on observation of the strengths and
weaknesses of student reports in the past few years.
• Make sure there is no silly repetition. This contrasts with this template which
deliberately contains many repetitions, but then it’s not a scientific paper.
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•
•
•
•
•
•
•
•
•
•
•
•
Do not give instructions. The last sentence is an instruction. Instructions might
be appropriate in the lab script or in this document, but not in a report. You are
not describing, you are explaining.
Avoid detailed arithmetical or algebraic calculations. Just give the
measurements, the results and how to get to the results. Rely on the reader
being a physicist who can check the working if needed.
Avoid jargon and abbreviations. However, don’t avoid the use of correct
scientific language: proper scientific language uses precise terms to avoid
ambiguity. For example, in the everyday world there is no difference between
mass and weight, whereas in physics there is.
Make sure that the text is in sentences and that you haven’t lapsed into notes.
It is not usual to ask questions, as it is attention-seeking.
Read your report critically and also try and persuade someone else to read it.
Delete all words that are not actually needed. For instance, delete the word
“very” in the phrase “a very strong magnetic field”.
Do not include subjective comments, for instance that the results could have
been better or that you didn’t enjoy the experiment. These can be put in the
section on Personal Comments at the end of your report and on the Blue
Opinion Cards in the laboratories.
Do not include the Aims and Objectives of the experiment as listed on the lab
script. These relate to teaching outcomes and are not relevant for the report.
Avoid repeating material from the lab script.
Consider when words should begin with a capital letter. Sentences begin with
a capital. So do proper names such as “Compton scattering” and “Young’s
modulus”. However, elements - for instance iron and argon - are not so
honoured.
Avoid the concepts of “can”, “could”, “possible”. Be specific and say what
you did.
Finally, remember that you are writing about a finished piece of work.
Therefore, do not say things such as that you ran out of time. Either you made
a measurement or you didn’t; talk about the measurements you made.
7. The Introduction
This section should introduce the reader to the report. A brief statement of why
the topic is of interest might be useful. Any historical background should be kept very
short as, while it may be interesting, it doesn’t contribute to the main aim of the
report. You might end with a brief summary of what you are going to include in each
of the following sections.
8. Organisation and Content
Remember that the reader is probably not familiar with the experiment. Your
target reader should be another literate scientist (an undergraduate physicist should be
one of those) whose knowledge of the experiment is what yours was when you started
it. So introduce the reader to the experiment. You can’t talk about the mirror until
you’ve told the reader that there is a mirror. Referring to a figure showing the
apparatus is often useful.
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A common problem is how to report an experiment that consisted of several
parts. For instance you might have used a Michelson interferometer to measure the
wavelength of a spectral line and then measured the splitting of a line and then studied
the bandwidth of a filter. It is really tedious to be presented with the theory (for each
part) then the apparatus (for each part) then the measurements (for each part) then the
results (for each part) then the errors (for each part) then the summary (for each part).
It is far better to consider all aspects (theory, apparatus, measurements, accuracy,
results, etc) of part one, (the wavelength) then all aspects of part two (the splitting)
then part three.
9. Some Technical Details
9.1. Headings
Notice the format and font of the headings and sub-headings in this document.
In the jargon of Word for Windows; the style of the main text is Body Text and the
style of the headings is Heading 1. Sub-headings are not in bold face. Notice the
numbering scheme and the position of full stops.
9.2. Units
Of course all quantities must have their units stated, as in 9.81 m s 2. Notice that
there is a space before the units and the units are in Roman (not italic) font.
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9.3. Errors
It is important, indeed essential, to discuss the errors i.e. the accuracy or
uncertainties of the measurements and results. Remember:
A measurement without an error is not a measurement
In most cases there is no need to have a section dedicated to errors. It is far better to
present statements about accuracy as you go along. For instance, state the accuracy of
the equipment when you describe it, give the accuracy of the measurements when you
describe them and give the accuracy of results as they are presented. Points on graphs
should be plotted with error bars.
You have a balance to strike. You can assume that the reader knows the basics
of error propagation so there is no need to spell out the formulae and arithmetical
calculations in detail, yet you need to convince a sceptical reader that you have done
things properly. For instance it is adequate, and indeed good style, to say: “The
current and voltage were measured to an accuracy of 1.5% and 2.5% respectively.
Combining in quadrature, this gives the power, P=IV, to 2.9%”. Any competent
physicist can check that 1.5 and 2.5 do indeed combine in quadrature to give 2.9.
However, leaving out the equation in examples similar to the one above would not be
appropriate, since the reader might not know that P=IV (!) is the correct equation. It is
usually important to explain what is the dominant source of uncertainty in the final
result.
A one-page summary and a full write up of PC1181, Data Analysis, is available
on the School teaching website. Remember to give numerical values to a sensible
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number of significant figures. An abstract claiming that your result for the
acceleration due to gravity is 9.8 ± 0.015643 will be laughed at; really, it will be.
9.4. Characters and Symbols
Greek letters and other special characters can be inserted into a word document
by using Character Map (they are in the font Symbol) or you can use Insert>Symbol.
For convenience several commonly required symbols are listed here so that you can
simply Copy and Paste them as needed. Superscripts and subscripts can be made by
typing the character, highlighting it, selecting Format, Font, then check superscript
or subscript; or, you can just press the appropriate buttons in the toolbar
Here are some characters etc that might be useful for copying; or you can just
pick the nearest equivalent letter in English (Roman) and then convert it to Symbol
font from the toolbar.
Some Greek characters:
α β π δ γ σ σ x 2 σx ω λ γ γ γ η π ψ χ ε ε θ φ ϕ µ
µ 4πε ρ χm ∑ Σ Λ Π Θ Δ Γ Ξ ∇ ∇ Ω
Some useful symbols:
± ≈ √ × ⊕ ∞ ∴ + ∗ − ∍ ∂ 〈 〉 ∼ ≤ ≥ ≠ ≡
Some useful expressions:
4.2 × 10 6 and (12.1 ± 1.5) × 108 and Tnitrogen .
Note that a minus sign “−” is not the same as a hyphen “-” .
2
ο
2
ο
ο
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9.5. Equations
All equations must be part of a grammatically correct English sentence. If an
equation needs to be referred to then it can be numbered as shown. Otherwise leave it
unnumbered. The following examples show how to neatly define symbols as you go
along and avoid an ugly list. Simple expressions can be entered directly from the
keyboard. Here are some examples:
The amplitude as a function of time is given by A = Ao sinωt, where ω is the
angular frequency.
The period, T, of a simple pendulum depends on its length, l, and is given by
T = 2 π √ (l/g),
(1)
where g is the acceleration due to gravity.
The gravitational force, F, between two point objects, of mass M1 and M2 is
given by
F = G (M1 M2 / R2),
(2)
where R is the distance between them.
Notice that symbols, A, t, T, l, g, F, G, M, R, are in Italic, but Greek letters and
superscripts and subscripts are in Roman. So it’s a bit tedious to type properly.
However, this is the usual convention and is the default in Equation Editor. Functions
such as log and sin are typed in roman font.
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For more complicated expressions and equations you can use Equation Editor
by doing Insert>Object>Microsoft Equation.
Here is equation (2), but now set using Equation Editor:
The gravitational force, F , between two point objects, of mass M 1 and M 2 is given
by
F =G
M 1M 2
(3)
R2
where R is the distance between them.
Equation Editor includes all sorts of useful goodies, including integral signs (
∫
a
x 2 dx = 23 a 3 ) and exponentials ( e − E / kT ).
−a
As you can see, Equation Editor is quite powerful, but it takes some getting
used to. A good way to learn is to experiment with the options. Also, make use of
colleagues and let them learn from you.
The default in Word is that a new line following an object (e.g. an equation) is
the beginning of a sentence and is automatically given a capital letter; this is often
wrong straight after an equation. To get the letter “w” in lower case in the word
“where” following equation (3), this auto feature has been turned off. (Go to
Tools>AutoCorrect>Capitalize first letter of sentences.)
It is important that all symbols are defined, but do this only once.
If you’re really stuck, leave a space and write the symbol or whatever in by
hand with fine black ballpoint. In this case make a photocopy of the page.
9.6. About Footnotes
The best advice to give about footnotes is to avoid them as much as possible1.
Put useful information in the text. Put references in the list of references at the end.
9.7. About Appendices
The best advice about appendices is in general to avoid them. Lab reports are
too short to justify an appendix at the end. If some calculation or derivation or detail
really is needed and does not fit comfortably into the main text then a short appendix
might be appropriate. The exception to this rule is when giving programming code; in
this case an appendix is the right place, as putting large reams of text into the main
body of a report is annoying.
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You can see here how annoying it is to look for a footnote that is attached to the main text.
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10. Presenting Information in Tables, Diagrams, Spectra and Graphs
Graphical information - which includes tables, diagrams and graphs and so on can be generated in several ways. You can a) use Word itself, b) use another package
and paste it in, c) scan it in from another document and paste it in, d) draw it neatly by
hand yourself and scan and paste. If you do copy a graphic from another document, it
is important that you should say in the figure caption where it has come from, i.e. give
a reference, otherwise you could be accused of plagiarism. It is also permissible to
take a graphic, cut around it and glue it onto your printed output. In this case make a
photocopy of the page. Note that it is conventional to label all diagrams, graphs and
spectra as “figures” and they should be numbered sequentially. Tables should be
numbered separately.
If possible put the graphics in suitable places in the main body of the text, near
to where they are referredto. If this is not possible put one or more at the end. It is
essential that all these graphics are numbered (as in this document) and that all of
them are referred to from the text.
Each graphic should also have a caption (see the illustrations). Captions are not
merely a title. They can be quite long and this is quite useful to help explain the
details. You can lock the caption to the graphic (to prevent splitting over a page) by
selecting the graphic, then Insert>Caption, enter your caption, OK. To make a
caption; select the table itself, Insert>Caption, type in the text. This method (usually)
prevents the caption from becoming separated from the graphic at a page break. You
can click on the text in the caption and edit it as needed. The tables are labelled: Table
1, Table 2 etc. The diagrams, graphs, spectra etc are labelled: Fig 1, Fig 2, etc as in
this document. The caption is in a smaller font that the main text. It is Times New
Roman 10 point (instead of 12 point). Notice that there is a bit of white space above
the graphic and below the caption; this is to help the reader separate the figure from
the text when reading.
A couple of final points. Firstly, a figure or table is not part of the main text; it
sits on the same page but is not part of the flow of the sentences. Secondly, every
figure or table should be referenced from the main text somewhere; this is done by
referring to it using its number. Table and figures are numbered separately, as they are
in this report.
10.1. Tables
Tables are a very useful way of presenting data, but avoid giving tables
containing lots of raw measurements. If a graph shows the data clearly there is no
need to present them also as a table. If you find yourself making a very big table of
reults, it’s time to present them in a graph. A table is often a good way of
summarising the results from several different measurements, so make good use of
them. To make a table select Table>Insert>Table…, and then specify the number of
rows and columns that you want. Table 1 is a simple example of some artificially
generated data. Notice that the table is numbered, referred to and that there is a
caption.
Current
Amps
0.1
Magnetic Field
Tesla
0.23
B2
Tesla2
0.053
Height of meniscus
mm
3.24
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0.2
0.3
0.4
0.5
0.6
0.46
0.66
0.87
1.06
1.27
0.212
0.436
0.757
1.124
1.613
3.41
3.60
3.97
4.32
4.81
Table 1. Height of the meniscus for different magnetic fields. The heights, measured with a
microscope, are accurate to 0.02 mm. The calibration of the magnetic field in terms of the current is
taken from reference [1]. Notice that you can put quite a lot in a caption, so they are quite useful. Also
notice the way in which the reference is used (see Section 14)
10.2. Diagrams
You can generate drawings by (a) using a package such as Draw or Paint and
pasting it in, (b) scanning a drawing and pasting it in or (c) draw the graphic using the
facilities within Microsoft Word.
Every figure must be numbered and it must be referred to from the text. Also
every figure must have a caption as illustrated in fig 1. Note that the caption can be
more than a title and in fact can be quite long.
Fig 1 was generated using the drawing package in Word (Insert, Picture, New
Drawing), but Powerpoint is probably better You just have to play with the line
types and arrows etc. Notice there is some white space above and below the figure.
The figure is numbered and referred to from the text. There is a caption.
A
B
laser
Fig 1. Schematic diagram of the Michelson interferometer. Mirror A is movable using a micrometer
screw gauge and a reduction mechanism. Mirror B has fine adjustments for alignment. You can give
quite a lot of information in the caption, where it is easier to relate to the figure than if that information
is in the main text. Notice also that captions go under the figure, not above it.
11. Graphs
Graphs are worth a thousand words for presenting data to a reader. We are much
better at digesting visual data than a table of numbers or a lot of detail explained in
the text. So it is rare for reports of experimental work to not include some graphs.
Graphs can be prepared by hand (not to be undervalued) or prepared by one of many
computer packages such as EasyPlot [2], Matlab [3], or Excel [4]. Remember to label
the axes and to add a caption. Remove unnecessary material such as plots of residuals,
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the fitted parameters, computer instructions etc. Display only the essentials and don’t
distract the reader with side issues. Remember that plotting error bars is an essential.
11.1. Inserting Graphs into your report
Fig 2 is an example of a graph generated using EasyPlot. You can save plots in
a variety of formats, but .jpg (or jpeg) is not a good choice as it makes lines look
blurry; jpg is fine for photographs. png or gif are much better choices, and eps is good
if you use LaTeX. Once inserted into your report, figures can be adjusted by use the
options available by right-clicking on the figure.
5.0
Increase of height with magnetic field.
The slope gives the susceptibility.
Height of meniscus, mms
4.5
A
4.0
3.5
B
3.0
0
0.2
0.4
0.6
Magnetic field squared, Tesla
0.8
1.0
2
Fig 2. Increase of height with magnetic field squared. The data are consistent with a linear relationship
and the slope is related to the susceptibility. The round points, B, are for a saturated solution and the
square points, A, are for a diluted solution as explained in the text. This is an example of a graphic
generated using EasyPlot but Matlab is much better. The data points are fictitious, but at least you can
see them clearly. Similarly, the axes are readable; it should be obvious that this is important.
12. The Discussion and Summary
It is good practice to end your report with a Discussion and/or a Summary. This
is preferred to a Conclusion. In the Discussion you can elaborate on any technical
points such as whether your measurements do or do not agree with each other or, in
some cases, agree with reference-book values. The discussion is where you discuss
the significance of your work, and that usually means interpreting it in comparison
with the work of others.
Don’t end your report with excuses such as the results would be better if only
more time were available. That’s nearly always true. The emphasis in a report is to
draw valid conclusions from the data actually available.
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13. General Appearance
Microsoft Word doesn’t always make a very good job of positioning graphics;
you can right-click on them to make sure they are so-called ‘inline’ figures, which
makes positioning them much easier. Inline figures don’t have little anchors, and they
don’t bounce around the document by themselves as you add or remove text. You can
print out your report either single sided or back to back. You can staple the pages of
your report together or you can put it in a plastic folder (available from the laboratory
technician). A useful tip is that if you can’t put a staple through your report, it is too
long.
14. About References
References serve several purposes: they acknowledge sources of information,
they lend authority to statements in the report and they tell the reader where s/he may
find more information. Using other people’s material without referencing it is
plagiarism. By judicious use of references to derivations of equations or detailed
descriptions of bits of apparatus you can even save yourself work! All reports should
have some references. References consist of two related parts, one in the text and the
other at the end of the report. In the text, for example, you may refer to a book as in
[6] or [7]. You can also refer to a specific page in a book using [6;p23] and later
[6;p45]. It is allowed to refer to the lab script [1], but only for the value of parameters
built into the equipment or for information that it is impossible to find elsewhere. If
you received a relevant piece of information from a person, you can reference and
acknowledge them as in: “A good technique [8] for measuring……”. Complementary
to what appears in the main text is the list of references that appears at the end of the
report under the heading “References”. Each entry in this list should be sufficient for
the reader to identify the source of information and usually should have a name, a
date, the title of the book or journal and a publisher. As an example of how to refer to
a scientific paper look at the one by Lyne and Lorimer [9]. Within this template
references are indicated by a number in square brackets and appear in full in the
reference list at the end of the document. There are other slightly different ways of
using references but use this one. The heading “References” does not have a number.
References to the web are contentious because, while books and journals exist
in perpetuity in libraries and can always be obtained, material on the web can be here
today and gone tomorrow. Also papers in journals are refereed and articles in books
are approved by the publishers, whereas there is often no such stamp of authority for
material on the web. However, web material can be very topical. Therefore,
references in scientific papers (that should stand the test of time) are rarely to the web.
Some more tips:
• The lab script is not a suitable reference
• Wikipedia is not a suitable reference
• Textbooks are usually suitable references right now
• Later on you will find yourself citing published papers more and more
Incidentally, the term Bibliography is used for a list of books and papers which
are of general interest and which are not referenced individually. This might be
appropriate in a more general article, such as a vacation essay, but it’s not used in
scientific papers, nor in lab reports.
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15. A Final Checklist
Here is a short checklist that’s worth going through when you’re writing a
report.
• Delete all the original text of this document if you’ve used it.
• Does it convince the reader?
• Does it conform with the guidelines?
• Check numbering of sections, figures and references.
• No silly repetition. No unnecessary words. No ambiguities.
• Run a Spell Checker, but look at the results.
• Read it.
• Get a friend to read it. Read someone else’s.
16. Assessment and Feedback
16.1. Length of the Lab Report
Students often put a lot of effort into their lab reports and they are often much
too long. There should be at most about 1500 words of text. Anything over 2000
words is excessive for an experiment that took only a few days. The whole report,
including the Title Page, the text and figures and diagrams etc, (but excluding a page
of Personal Comments) should not exceed 8 pages. This template is well over 5000
words so your report should be less than half this. However, this template has only
one table and only 3 figures, your report could well have more. Undergraduates often
say they struggle to fit everything into this word limit; this is nearly always due to
excessive language. With practice you will be able to compress twice the information
into half the words; so practice doing that.
Note it is not necessary to include everything that you did. It is more important
to present some result(s) in an honest and convincing way.
16.2. Assessment
The assessment of your report will concentrate on how well it stands up as a
scientific document, particularly how well it communicates the results of your
experiment to a reader. In normal lab marker will try to ignore how well you actually
did the experiment because this was previously assessed in the interview.
You might like to bear in mind that by far the most common comment made by
markers is that students seem to have not read the guidance and instructions. So read
this advice carefully and take note.
16.3. Late Reports
Working to a deadline is an important skill, i.e. one that will matter in any
decent job you do. Any report handed in after the deadline will be marked as usual
(though not as a matter of urgency), but there will be a penalty. Note that a report (of
adequate standard) is required, even if late, in order to satisfy work and attendance
requirements. In real life it is nearly always better to have an adequate report on time
than a great report that’s too late.
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Acknowledgments
Any acknowledgments should be at the end of the report before the references.
You might like to thank your partner, lab technician, tutor etc. By convention there is
no need to number this section. For example, I would like to thank all those students
whose reports I have read in recent years and thus obtained some knowledge, albeit
limited, of the difficulties of writing laboratory reports.
References
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
Hook, J. 2002. Low Temperature Resistance, 2nd yr lab script, Physics Dept,
Manchester Univ.
EasyPlot, Scientific Plotting and Data Analysis, by Stuart Karon, Spiral
Software, Box 2537, Chinle, AZ 86503.
MATLAB, Version 5, The Math Works Inc, Natick, Mass 01760.
Microsoft Excel, Microsoft Corporation.
Matlab Least Squares Fit, James, R, Dept Physics, Manchester University.
Squires, G. L. 2001. Practical Physics, 4th Ed, Cambridge University Press.
Kaye, G. W. C. and Laby, T. H. 1995. Tables of Physical and Chemical
Constants, 16th ed., Longman.
Cunane, P. Private communication.
Lyne, A. & Lorimer, D. 1994. Nature, 369, 127
Length and Date
The following is not really part of a scientific paper, but can usefully be
included in a lab report for teaching purposes.
The number of words in this document is 5559 .
This document was printed on 20/02/2014 at 22:31.
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Personal Comments
Comments such as “I enjoyed the experiment”, “I think this is a good
experiment because…”, and any such personal opinions are not part of a scientific
report and must not be included in your report.
However, you may, if you wish, place at the back of your report a separate page
entitled “Personal Comments”. This will not be treated as part of the scientific paper,
but as information for markers. Relevant information might be that you have been
working without a partner. You can also ask the marker for feedback on specific
points such as “I was unsure about section 3; is it too long?”, “I didn’t know whether
or not to include xxx”, etc or make any comment you like. We hope that this will
provide better feedback for you.
Of course comments can be made at any time anonymously by filling in the
Blue Comment Cards available in the laboratories.
Comments on this Template
This template may contain bugs and weakness as well as good advice. Please
send comments and corrections to:
Dr. Hywel Owen
email: hywel.owen@manchester.ac.uk