Investigation Pack
Year 13 Advancing Physics
Contents:
Timeline
Choosing a topic
Preliminary work
Doing your investigation
Writing it up
Investigation checklist
Dealing with uncertainties and errors
The mark scheme
List of titles
Timeline
Fill in the dates that your teacher gives you:
Date
Submission of provisional titles
Submission of apparatus list
Practical work
Submission of draft report
Submission of final report
Choosing a topic
A good topic is…
 Something that you are interested in
 Something that makes you think 'why does that do that?'
 Something that is not a standard practical
 Something that you do not know the answer before you start
 Something that means that you will have to make something
 Something that has scope for development
 Something that mans you can make quality observations or take measurements or both
 Something that includes physics!
A good investigation will incorporate a large number of the above points, but not necessarily all of them.
Start by looking around you and thinking about interesting things that you see. These tend to lend
themselves to mechanical properties type investigations (hair, spaghetti…), music (physics of the flute,
boxes under guitar strings) and such like. Alternatively it could be something that you have read about, a toy
you want to investigate, something you want to make.
The MOST important characteristic of this title is that it is OPEN. It must go somewhere, have room for
development or related work.
A list of titles is attached but you should be careful – just because it is on the list does not guarantee that you
will get on well with the idea. It will be tempting to find a teacher and say ‘I am thinking of doing X, what did
‘they’ do for that?’ but that is not the point. Of course your teacher could tell you a method but that will not
make a good investigation and we aren’t going to tell you so don’t ask.
You need to discuss you titles with your teacher AT THE EARLIEST OPPORTUNITY.
Preliminary work
You MUST try it out as soon as you can. TRUST US on this point. It is not just enough to assume that you
will be able to get some results.
There is ABSOLUTELY NO SUBSTITUTE for getting the equipment out and trying it out. You can do that at
any time – just ask.
This work will seal the fate of your choice… you will either decide to go ahead or choose something different.
If you have decided to go ahead then you need to do 3 things
 Collect an exercise book to use as your lab notebook, or continue with the one that you used for your
sensor project
 Plan what you will do in detail
 Order equipment
 Do a risk assessment
We will need to see that the above is complete before you can start. You need to get your equipment order
in well before you plan to start. Bear in mind that we have a limited number of some items like oscilloscopes
and signal generators. Talk to a teacher about what you need.
Doing your investigation
This is the fun part!
You need to make full use of all your lesson time. You may do work outside of lessons, including lunchtime
and after school after clearing it with a teacher. You must NOT work in the lab on your own without the
knowledge of a member of staff.
Things to do EVERY DAY
 Write the date and record everything that you DID and THOUGHT in your lab notebook.
 Don’t forget to consider/write down uncertainties in all the measurements that you make.
 Draw graphs of any data that you collected.
 Make a note of questions to ask your teacher about.
Things to do AT TH END OF THE FIRST WEEK
 Write a brief summary in your lab notebook of what you have found out
 Discuss how far you have got with your teacher
 Make a new plan for the final week
Things to do AT THE END OF THE SECOND WEEK
 Dismantle all your equipment and return it in a neat fashion to the prep room
 Discuss with your teacher what to do with any apparatus that you have constructed
 Make sure that your work area is clean
 Make sure that you have all the information that you need to write up the draft. This includes the PHYSICS
of what happened. See your teacher if you are not sure.
Writing it up
Remember the lessons you learned writing up your Research and Report.
If you have been writing up what you have been doing EVERY DAY in your notebook then writing this up will
be a breeze. The reverse is doubly true.
The structure of your reports is up to you but may be as follows

An aim

A summary

A brief outline of the physics involved in explaining what is going on

A risk assessment.

An account of what you did, including all the preliminary work, blind alleys and wrong turns – do NOT
sanitise your work. A diary format works well but it is up to you.

A section that says how you dealt with uncertainties

An analysis of the results that will have graphs and their interpretation

A conclusion which reflects on the outcomes of the investigation in a critical way.

An appendix that has all your results tables

A bibliography if applicable
Alternatively print out the following checklist from the website and use that.
Investigation Checklist

Write a clear aim that states the question, problem or situation that you are investigating.
Write a summary of 200 words or less that gives an overview of what you did.
Write down what you did, including all the blind alleys, things that didn't work etc. A diary format is a
very good way of writing up, as long as you kept a record of what you did each day.
Include a risk assessment - make it clear how you gave due regard to safety
Explain clearly the physics of what you were trying to do
Think about the precision of your results. How many decimal places should you use?
Include details of any observations that you made - photos are great also. Careful
observations/diagrams are as good as numerical data
Tables of data should go in an appendix at the back of your report and must NOT be included in the
text.
Graphs of the data should be integrated into the account, as should calculations based on your data
ALL numbers should be quoted with an uncertainty as shown in your practice investigation pack available on the web or through me. If you do calculations you should carry the uncertainties through
to give an uncertainty in the quantity that you have calculated - see me if you don't know how to do
this.
Explain how you dealt with uncertainties and the steps that you took improve the precision
THINK about the graphs that you plot, make sure that they are correctly labelled and always
comment on them.
All points on all graphs must have error bars on them
Identify and explain any discrepancies between results
Explain, using physics, what you have found out. How certain can you be of what you think?
Think critically about what you have done and comment on the limitations. Saying 'I didn't have
enough time' will not suffice.
Dealing with uncertainties and errors
You, the experimenter, will go and measure some physical quantities numerically (using some piece of
equipment to do so). You make a measurement. The measurement is necessarily somewhat different than
the true value of the physical quantity.
First, we need to define some terms:
 Accuracy: This is the extent to which your measurement is in fact close to the true value. If you do
not a priori know the true value, then it may be difficult to determine to what extent your
measurement is accurate.
 Precision: This is the extent to which you can specify the exactness of a measurement. For
example, to report that the time is about 3 PM is less precise than to say the time is 3:02:45. Being
more precise does not always imply being more accurate.
 Statistical (Random) Uncertainty: This is a key idea. The statistical uncertainty of a measurement
is the uncertainty that reflects the fact that every time you make a measurement, you must, be
necessity, measure a slightly different quantity each time. The tendency for a measured value to
"jump around" from measurement to measurement is the statistical error.
 Systematic Uncertainty: This is uncertainty and error in your measurement caused by anything that
is not statistical uncertainty. This includes instrumental effects, not-taking things into account (will the
change in barometric air pressure impact this measurement?) and gross (stupid) errors.
Any measured quantity or calculated constant requires 3 items in order to specify it completely:
(1) a numerical value
(2) a unit
(3) an indication of the reliability of the ascribed value.
Item (3) means the uncertainty or systematic error.
Note that the two words, 'uncertainty' and 'error' are often interchangeable. Strictly 'uncertainty' is best used
to represent a range which contains the true value, perhaps with a statistical confidence, whereas 'error' is
best used to cover measurement deficiencies such as systematic differences (errors).
An example of a fully specified statement might be: acceleration = 13.4 ± 0.2 km s-1
1.
Absolute, Relative and Percentage Uncertainties/Errors
Statement: time for object to fall = 14.32 ± 0.04 s
The 0.04 is referred to as the absolute (time) uncertainty in the measurement. The relative uncertainty is
simply calculated as
0.04 / 14.32 = 0.0028
The percentage uncertainty = relative uncertainty x 100%
= 0.28%
So we can re-express the statement as:
time to fall = 14.32 s ± 0.3%
1.a. Quoting Uncertainties
(a) The uncertainty must be quoted to the same number of decimal digits as the value. e.g. 14.32 ± 0.04
and not 14.32 ± 0.041
(b) Knowing the uncertainty in a quantity immediately reveals the number of significant digits its value
should contain
e.g. 9.77 ± 0.01 m but not 9.7742 ± 0.01 m
since the uncertainty of ± 0.01m clearly indicates that the third significant figure is uncertain and thus there is
no point in writing down the 4th, 5th, etc.
2. Types of Uncertainties and Errors
Uncertainties are mainly of two types, systematic and random. There does exist a third type, blunders, but
they must be discarded when correctly recognised.
2.a. Systematic errors
Often these are the most difficult to deal with since you may not even be aware of their existence. They
cause a series of measurements to be always too high or too low rather than randomly scattered about the
true value; e.g. a shrunken ruler will always give length measurements which are too high.
Systematic errors must be carefully watched for and if possible eliminated or turned into random
uncertainties; e.g. in measuring a temperature difference, exchange the two thermometers and take a
second reading thereby eliminating zero errors.
2.b. Random Uncertainties
These may result either from the random varieties (often referred to as fluctuations) in the measured quantity
itself (e.g. the emission of alpha, beta or gamma rays from a radioactive source or from the variations in
measuring instruments and/or the experimenter. This simply means that repeated measurements are
unlikely to give precisely the same value each time. Rather a spread of values will be obtained and it is from
this spread or scatter that the uncertainty in the measured quantity is best determined. You can turn this
argument around and state that the best way of accurately determining the uncertainty in any measured
quantity is by repeating the measurement many times.
The next two sections, however, will consider situations in which a detailed treatment of measurement
scatter is not relevant.
2.c. Non-random Measurements
If you make a series of measurements and they all have the same value (see previous section) this indicates
that the instrument used for the measurement was possibly not sufficiently sensitive for the use intended and
you might then consider whether your choice is appropriate.
This does not mean, however, that there is no uncertainty in the measurements.
Example:
Using a vernier the following measurements were made of the diameter at different points along a
brass rod; 1.42 cm, 1.42 cm, 1.42 cm, 1.42 cm, 1.42 cm. Clearly any variations in diameter are too
small for the vernier to detect. This does not mean that there is no uncertainty in the result, but rather
that it is not greater than half the smallest division that the vernier can measure, viz. 1/2 x 0.01 cm =
0.005 cm.
If the length had been greater than 1.42 cm the venier would have read it as 1.43 cm; if it had been
less than 1.415 the reading would have been 1.41 cm.
The result of this measurement is, therefore, written as 1.42 ± 0.005 cm
2.d. Limited Sampling
On many occasions you will not be in a position to repeat a measurement many times. For example,
recording the temperature of a cooling body; you measure single temperatures at specified times. Here you
must use your own judgement in determining how accurately the temperatures were measured. Under ideal
conditions the uncertainty is likely to be ± 1/2 of the smallest divisions of the instrument used. Note, however,
this is likely to be the minimum uncertainty and that systematic or instrument errors, may be somewhat
higher.
It is good practice to examine the manufacturers specifications for the instruments you use.
Time restrictions limit you to only a few, say 3 or 4 repeated measurements
Example:
Four length measurements of a rod were recorded as : 0.041, 0.044, 0.044 and 0.045 m. There are
two alternative approaches in calculating the uncertainty.
(a) Take the uncertainty as half the difference between the highest and lowest readings
= ± (0.045 - 0.042)/2 = ± 0.002 m.
(b) Calculate the average deviation for the four readings
For the above example this is ± 0.001 m which is half the value calculated in (a). The disadvantage
of this method is that calculating the spread in small samples using average deviations (or standard
deviations) is extremely dubious.
3. Manipulation of Independent Uncertainties
You will often have to calculate a quantity that depends on a number of measurements you have made, each
having some uncertainty. You need, therefore, to understand how the individual uncertainties combine. The
section below describes a very simple way of doing it but which will overestimate uncertainties.
3.1 The Less Precise Way
Addition and subtraction Let L = x+y-z with dx, dy and dz the absolute uncertainties in x, y and z
respectively.
dL = dx + dy + dz
Note that the change in sign of dz is justified by the following arguments:
Maximum value of L will be given by
(L+dL) = (x+dx) + (y+dy) - (z-dz)
= (x+y-z) + (dx+dy+dz)
and the minumum value of L by
(L-dL) = (x-dx) + (y-dy) - (z+dz) + (x+y-z) - (dx+dy+dz)
i.e. dL = dx + dy + dz
Absolute uncertainty in sum = algebraic sum of absolute uncertainties in the individual terms.
Example : Suppose a = (2.1 ± 0.1)m, b=(3.4 ± 0.4)m and c = (0.82 ± 0.01)m
If S = a + b - c What is dS?
dS = da + db + dc = 0.1 + 0.4 + 0.01 = 0.51 = 0.5
thus S = 4.7 ± 0.5m
Products and quotients
Let L = x(y/z)
Log L = log x + log y - log z
dL/L = dx/x + dy/y + dz/z
Relative (or percentage uncertainty) of a product and/or quotient = sum of the relative (or percentage
uncertainties) in the individual terms.
Examples:
Suppose a = (2.1 ± 0.1)m, b=(3.4 ± 0.4)m and c = (0.82 ± 0.01)m
If S = a x b/c What is dS?
dS/S = da/a + db/b + dc/c = 0.1/2.1 + 0.4 /3.4+ 0.01/0.82 = 0.18 = 18%
thus S = 9.0 ± 18% or 9.0 ±1.5m
Powers
Let L = xa yb
Log L = a log x + b log y
dL/L = a dx/x + b dy/y
Relative (or percentage) uncertainty = sum of the relative (or percentage) uncertainties in each term
multiplied by the corresponding power index.
NB If a parameter is raised to a high power then its contribution to the total error is increased by a factor
equal to the value of the power. It is important that the parameter is measured with increased accuracy in
order to keep the total error relatively low.
Examples:
Suppose a = (2.1 ± 0.1)m, b=(3.4 ± 0.4)m and c = (0.82 ± 0.01)m
Suppose S = x2y3 where x = 4.0 ± 0.2, y = 2.2 ± 0.3 What is the value of dS?
dS/S = 2(dx/x) + 3(dy/y) = 2(0.2/4.0) + 3(0.3/2.2) = 0.1 + 0.4 = 50%
thus S = 170 ± 50%
NB The above technique for the manipulation of uncertainties leads to values which are generally too large.
3.2 The Precise Way
By simply adding the absolute uncertainties it is assumed that the uncertainties in dx, dy and dz add in the
worst possible way. If dx, dy and dz are independent uncertainties then this will rarely happen. A more
suitable way of calculating the uncertainties is as follows:
(dL)2= (dx)2 + (dy)2 + (dz)2
for products and quotients:
(dL/L)2 = (dx/x)2 + (dy/y)2 + (dz/z)2
and for powers:
(dL/L)2 = a2(dx/x)2 + b2(dy/y)2
Uncertainties, so calculated, are usually referred to as the most probable uncertainty
4. Error bars on graphs
You must account for the uncertainties in your measured points by representing these uncertainties as error
bars on your graphs. In nearly every experiment, you are varying some quantity, X, and the measuring the
impact on some quantity, Y. Measure the uncertainties in X and Y. Then plot Y vs. X with bars on Y and X to
show how uncertain the measurement was (see graph below). This is what a physicist means by error bars.
A graph without error bars is just plain wrong. Sometimes the size of the bar is very small - that's ok.
Once you have plotted the points, do a fit to some function (usually a line) that describes the physics you
expect, or just see what line you get. Remember that if you ask for a polynomial, you will get one. The
trendline is not 'it', it is not the point of the exercise.
Once you have this you need to address the following question: is the best fit a good fit. In other words,
does the model fit the data to within the uncertainties prescribed by the error bars. This is the critical
question for the experimental physicist. Your goal is not to measure a number. Your goal is not even
to measure the "right" number. Really, your goal is to determine if the physical model is supported
by the data.
In my opinion, if you take this notion to heart, you will understand the soul of experimental physics. To do this
you must numerically answer the question: "Does the data fit the model to within the uncertainties on the
measurements?"
Sometimes, you may not know what it is supposed to do and what kind of line the physics would suggest. In
that case you are looking for a relationship between two quantities and to work out what that is you have to
find something to plot that gives you a straight line, e.g. y against x 2. If you get a straight line, that is the holy
grail of physics - you can say that y is proportional to x 2 - you have discovered a law that governs those two
quantities. Your next task is to work out WHY is should be x2 and not x3 or 1/x.
PHYSICS B (ADVANCING PHYSICS)
ADVANCED GCE
UNIT 2863, Component 02 Practical Investigation
Coursework Assessment Form
Examination session
Year
June
Centre name
Gosford Hill School
Centre number
6
2
2
3
5
Candidate number
Candidate name
Initiative and independence:
A copy of this sheet must be attached to each candidate's work as a record of the assessment. The full criteria on which the
assessment should be based can be found in the Teacher Support: Coursework Guidance.
Problem:
Use of
There is clear
The definition of
The problem has resources:
analysis of the
the problem is
been defined in
To good effect;
Some resources
Required direction
problem.
sound but lacks
simple terms
advice and
put to good use
Appropriate
some detail
resources were
variables are
well used.
selected for
A
Experimental
investigation.
A reasonable
Some evidence
design
A thoughtful plan
plan was made.
of planning
Simple apparatus
was constructed
Careful choice of Equipment,
used in a direct way
(i)
equipment,
methods and
Planning
methods and
techniques are
Independence
The student's
Help and advice
techniques
adequate
(ii)
Personal
own ideas are
given were
Safety measures
Safety and
responsibility was
sound, and
usually acted
are somewhat basic
resources
Safety
taken for plans
advice given
upon
Some attempt is
and decisions.
was acted upon
Safety was
made to address
given due
safety
regard.
(i)
(ii)
/5
Use of physics
B
(i)
Appropriate
activities
(ii)
Practical
skills and
techniques
In devising the
strategy:
Knowledge of
physics is used to
inform decisions
about the progress
of the investigation
Experiments
A good range of
experiments,
showing
progression and
development. The
potential of the
experimental work
has been fulfilled
Some
knowledge of
physics was
used in planning
but some work
was empirical.
A related set of
experiments is
used, or some
aspects of one
experiment are
investigated.
Some of the
potential of the
work has been
developed
The work was
largely empirical
Experimental
work relates to
the task, but is
limited in certain
important
respects
(i)
Some practical
skill is shown;
the work is
competent.
Apparatus used in a
direct way
Experimental
design
There is
evidence of
experimental
design
There is some
evidence of
experimental
design
Little knowledge of
physics is brought
to bear
Effects:
Effects which
might affect
results are seen
and dealt with
Effects that
might affect
results are
commented
upon
Effects that might
affect results are
not considered
(ii)
/5
Additional comments to support and explain ratings A and B
/5
In executing
experiments:
Practical
knowledge and
skill are put to
good use
/5
Observations
Observations &
measurements made
with appropriate
precision
The number and
range of results are
appropriate
Communication
C
(i)
Record of
observation
s
(ii)
Quality of
report
Record of
observations
The collection and
recording of data are
well organised
Uncertainties
The limitations on
accuracy, are
appreciated. Steps
are taken to
minimise
uncertainties
Observations
are recorded
clearly. The
number and
range of results
are satisfactory
Observations
are those
expected for
the task, but
may be
lacking in
detail, range
or precision
The collection
and recording of
data are
satisfactorily
achieved
Tables of
results lack
significant
details
Some steps are
taken to
minimise
uncertainties
Little attempt
has been
made to
reduce
uncertainties
Evaluating evidence and drawing conclusions
D
(i)
Evaluation
(ii)
Conclusion
s
Discrepancies
Discrepancies or
anomalies are dealt
with. Error bars have
been used effectively
on graphs to reflect
the uncertainties
Limitations of
methods
The limitations of the
experimental
procedures used are
fully appreciated
General trends
in the data are
established
using
appropriate
techniques
There is some
attempt to
identify trends
in the data, but
the analysis
lacks depth
Relationships
proposed are
consistent with
the evidence
Expected
relationships
are assumed
to be present
though they
may be
unsupported
by the
evidence
Some
discrepancies
are commented
upon
The main
limitations of the
experimental
procedures are
appreciated
Discrepancies
are largely
ignored
There is little
awareness of
the limitations
of the
experimental
procedures
used
(i)
/5
RATING TOTAL
/5
Critical thought
The work shows
evidence of critical
and connected
thought
Physics
Qualitative results
are interpreted
with care and
insight. Basic
errors in physics
are avoided
Conclusions
The uncertainties
inherent in the
data are reflected
appropriately by
the tentative
nature of the
conclusions
The work is
interesting,
achieving results
new to the student
(ii)
/5
/40
Additional comments to support and explain ratings C and D
Assessors signature :
Work is generally
neat and orderly
The report is
essentially a
summary of
the work done
Graphs are basic,
neat and without
distracting elements.
Attempts are made
to choose the most
appropriate plots
Tables and
graphs are
presented,
perhaps
without much
comment
The quality of
English is
acceptable
The quality of
English just
adequate
The work shows
progression and
development.
The progress
of the task
was not
affected by
the effects
observed
Results are given
some physical
interpretation, even
if this reveals minor
misunderstandings.
There are few errors
in basic physics
The work is
largely
empirical with
little attempt
to interpret
the physics.
Conclusions, though
supported by the
evidence, may not
be qualified as
necessary
Conclusions,
which may be
qualitative,
are limited
and focus on
the more
obvious
results
(ii)
/5
Relationships
Relationships
proposed are
consistent with the
evidence and
supported by
underlying principles.
Graphs and
tables:
Graphical plots are
well-chosen, to
display results
effectively. Graphs
and tables are
correctly labelled
Use of English:
The quality of
English is good
(i)
Analysis
The results are well
analysed, to reveal
the underlying
relationships
Presentation:
The report is
concise and
presents results
with impact and
clarity
Date :
List of titles
1 The factors causing variation in the attenuation
of perspex.
2 Flow of water over notches and weirs.
3 Contraction of adjacent turns of a coil due to
current through them.
4 Investigation of factors involved in flow of
powders and crystals.
5 Investigation of light from a 1.5 V bulb and
relative amounts light of different wavelength from
it.
6 Load/speed variation of parachutes.
7 Study of splashes.
9 Corona discharge.
10 Forced convection.
11 Fibreglass joints.
12 Araldite bonds.
13 Audio percussion induced vibrations in metal
rod.
14 Creep in copper wire.
15 Effect of shelving on breaking of waves.
16 Strengthening of ice by sawdust.
17 Aerodynamic forces on a motor car.
18 A liquid flow meter.
19 Piezo electric effect.
20 Use of eddy currents for >n-destructive testing.
21 A wind powered generator.
22 The formation of a water tornado.
23 Electrostatic particle precipitation.
24 Water impact with a plane surface of water.
25 Distribution of air-borne pollution.
26 An electrical analogue for water flow through
locks.
27 Pouring - factors making the ideal spout.
28 Construction and use of a variable-interval
coincidence counter for study of short-lived
isotopes in a radioactive decay.
29 Factors which might be involved in the hanging
of a chain of uniform mass/unit length.
30 Smoke rings.
31 The effect of different periods of short-circuiting
on the rate of recovery of a dry cell.
32 Pressure/volume relationship of a rubber
balloon.
33 Behaviour of drops on a hot plate.
34 Feasibility of solar energy.
35 Optimum aperture of a pin-hole camera
36 Absorption of microwaves.
37 A study and analysis-of rotational vortices.
38 The control of sound in rooms.
39 The effect of internal pressure on the
performance of a football.
40 Conductivity of electrolytes in wood.
41 Absorption of liquids by filter paper.
42 Shapes of water columns flowing from tops.
43 Shaded magnetic probes.
44 Ionisation of air and van de Graff generators.
45 Design of an automatically operating burette.
46 Use of a photo-sensitive device as a
photometer and application to light emitted from a
light bulb.
47 Energy stored in a clock spring.
48 Investigation of cling wrapping: Why does it
cling?
49 The production of a pump using the movement
of ions in a magnetic field.
50 Magnetic suspension.
51 Temperature in a flame.
52 Absorption of electromagnetic waves by glass,
53 Motor and dynamo effects on conducting
liquids.
54 The sound of sea as heard in sea shell Is.
55 Performance of a fan
56 Lightening valve rocker arms to improve
engine performance.
57 Phase change in an induction motor.
58 Fringes in draining soap Films.
59 Heat pulse in a rod
60 Hovercraft.
61 Properties of foam plastic.
62 The singing of a kettle.
63 Acoustics of a large room
64 Relationship between the wavelength and
changing concentration in a fluorescent substance
65 Rotating shafts.
66 Craters.
67 Making an accelerometer.
68 The shape of a drop.
69 Holes in magnets.
70 Oscillations of wire rings.
71 Does a flame conduct electricity?
72 Thermocouples using various metal junctions.
73 Sound frequencies from metal plates.
74 Quantitative transmission of radiant heat.
75 Puncture properties of paper.
76 Effusion of moving gases.
77 Plastic properties of leather.
78 Transmission of sound through water.
79 Effect of pressure on a sparking plug.
80 The settling rate of metallic particles.
81 Investigation into electrostatic load speakers.
82 The effect of shape on the efficiency of a
rowing blade.
83 Some physical properties of a brake fluid.
84 comparison of the thrust of a propeller with its
rate of turning.
85 To investigate the stream-lining of fish as
related to their passage through water.
86 Measurement of capacitance using a
monostable circuit.
87 Strengthening ice by paper.
88 Investigation of windmill design.
89 Perfect perforations.
90 Methods of using waves and tides to produce
electricity; using models in the laboratory.
91 Harmonics in a guitar.
92 Behaviour of bubbles rising in liquids.
93 Beta-particie emission energy spectroscopy.
94 Properties of aerial arrays.
95 Variation in range of alpha -particles in air at
low pressure.
96 Does water absorb ultra-violet light?
97 An experiment in the synthesis of speech.
98 Nature of water vortices.
99 Three-dimensional waves in jelly.
100 Performance of a model diesel engine.
101 Effect of wavelength on the angle of refraction
of water ripples.
102 Dust and static as a problem with
gramophone records.
103 Multivibrator used as a motor speed control.
104 A braking system using electromagnetic
induction.
105 Properties of a vibrating string using
Lissajou's figures.
106 Factors affecting the lift of an aerofoil.
107 Magnetic amplifiers.
108 The effect of a grid between two electrodes in
partly ionic medium.
109 Back-scattering of beta particles.
110 Strength and domain structure of magnets at
different temperatures.
111 Hull design.
112 Resonating laminas.
113 Transmitting still pictures.
114 interference produced by electric switches.
115 Sound damping by Polythene.
116 Fishing rod strike times.
117 Path of a ball through air.
118 The effect of the thickness of fibreglass
logging in the temperature distribution along a
brass rod, heated at one end.
119 Vibrating times of certain wires after being
given initial displacement.
120 Electrostatic cooling.
122 Absorption spectra of plant pigments.
123 Pitch of xylophone bars.
125 The catapult, methods of measuring
efficiency.
126 To show stress positions in sheets.
127 Visibility of colour in the dark.
128 The creep of lead.
129 Use of a search coil to measure magnetic
fields at high Frequencies.
130 Eddy current heating.
131 properties of 4 ply wool which make it useful
for woollen garments.
132 Some useful properties of nylon fabric.
133 Strength of ice girders.
134 Intensity of radiation from a GHz oscillator.
135 Electronic feedback.
136 Aeronautics of a fly,
137 Load bearing properties of a spider's web.
138 Minimising feedback in a microphone system.
139 Analogue for polarising effect of hills etc on
unpolarised UHF.
140 Effect of electromagnetic waves on
permittivity.
141 Effect of smoke particles on the wavelength
of sound.
142 Design, operation and uses of spectrum
analysis for musical instruments.
143 Frequency of vibrating warm liquid
containers.
144 A water trough as an accelerometer.
145 Factors affecting the suitability of materials for
use in umbrellas.
146 Viscosity of fluids in flywheel bearings.
147 Potential variation in a tank of conducting
liquid.
148 How the mass of an air track vehicle affects
its performance.
149 Shapes and oscillations of soup bubbles.
150 Creep in rubber.
151 Support of a ball I in a jet.
152 How long does the flash from a bulb last?
153 Investigation of the behaviour of a
commercial radiometer.
154 Contact resistance.
155 Switching speed of a toggle switch.
156 Forces in the skin of a balloon.
157 Schlieren photography.
158 Capacitor microphone.
159 Comparison of three loudspeakers.
160 Electrical impulses in skin.
161 The effect of different pitches on the overall
performance of a marine propeller.
162 The velocity of particles from an 241-Am
source.
163 Efficiency of a 12 volt motor.
165 Efficiency of airscrews.
166 The spiralling flight paths of various winged
seeds.
167 Electrical resistance of ice + water with salt
added.
168 Behaviour of wood under stress, strength and
rigidity of different beam and girder constructions.
169 The dashpot method of damping.
170 The electrical characteristics of a solar call.
171 The behaviour of large waves in a narrow
channel.
172 Variation of friction with the relative velocity of
two bodies in contact.
173 Variation of speed of a mechanical wave in a
wire.
174 Shattering of glass.
175 Noise in a hot resistor.
176 Restitution time of a steel ball on an iron
surface.
177 Paddle wheel performance.
178 Effects of detergents an the reflection of light
by cotton.
179 Relationship between humidity and velocity of
sound in air.
180 Water rise up polymer threads.
181 Acoustic properties of plastic forms.
182 Intrinsic conduction of thermistors.
183 Vibrating plates.
184 Photoelectric effect in semiconductors.
185 Effect of load on cells.
186 The bursting of a balloon.
187 Microwave for ranging and detection.
188 Oscillations and deflection of model
suspension bridge.
189 Deflection of water droplets at high voltage.
190 Effect of magnetic fields on electrolysis and
semiconductors.
191 Electrical weighing machine.
192 Damping of oscillations in liquids.
193 Efficiency of a fan belt.
194 Finding the current in a floating aluminium
ring.
195 Venturi principle.
196 Electromagnetic f lowmeter: using the Hall
effect in liquids to measure the velocity of ionic
fluid througha tube.
197 Investigation of sails.
198 The thermoelectric effect in metal wire and
foils.
199 Action of salt on ice with reference to roads.
200 Why do soap films burst ?
201 The practicality of recharging dry cells.
202 The effect of internal energy on stress/strain
relation.
203 Effects of a black and white disk producing
colour.
204 Ultra violet absorption by water.
205 High velocity impacts in sand.
206 Effects of concentration and temperature on
conductance of a solution.
207 Effect of magnetic field on current flowing
through a thermionic diode.
208 To find the best 'tap' to polish plate glass.
209 Hall voltage in electrolysis.
210 Characteristics of an LDR.
211 Sedimentation.
212 Bumping and bol I;ng.
213 Efficiency of a water wheel.
214 Adhesive properties of 'blu-tack'.
215 Conductivity of damp wood.
216 Friction reduction by oil and grease.
217 Add-on multi-beam display unit for
oscilloscope.
218 Rotating liquid surfaces.
219 Measuring forces electrically.
220 Cross linkages in rubber.
221 The physical characteristics of a system
which measures distance accurately using light
interference.
222 The flight properties of a shuttle cock,
223 Rheological gel strength and other physical
properties of solutions of gums used in food
industry.
224 Polarisation of scattered light.
225 Efficiency of a bow.
226 Soil dispersion by falling water.
227 Origins and forms of waves at interfaces.
228 Construction of an air flow meter.
229 Fresnel lenses for 3 cm waves.
230 Paper clips.
231 Resistivity and dislocations.
232 Conductance through low pressure gas
233 Forced oscillations in mechanical resonating
systems.
234 Electromagnetic clutch.
235 Dam spillways.
236 Physical efficiency of common surfactants.
237 Factors affecting refractive index of liquids.
238 Projecting drops from a nozzle.
239 Functional properties of copper pipes on
cooling.
240 Absorption spectra of plant pigments.
241 To make and use a photometer to investigate
the luminous intensity of a lamp.
242 To try and find an ideal air track slider.
243 Building and testing an electrostatic speaker.
244 To find the best aerial design to give the
strongest signal for horizontally polarised radio
wave reception.
245 Crystal growth.
246 The bouncing of relay contacts.
247 Friction of shoe sales.
248 The string telephone.
249 Effect of cooling fins.
250 Rate of condensation of water etc with an
applied electric field,
251 Electronic tuning device for a guitar.
252 Factors affecting the efficiency of infrared
absorption.
253 Properties of plastic cups.
254 Cracks in glass rods.
255 The effect of make up on ultra violet light.
256 To study the effect of soaking in water on the
tensile strength of cartridge paper.
257 The natural radioactivity of rocks.
258 The effect on the rate of combustion of a
material of on electric field.
259 Effect of liquids on the static bending of balsa
wood
260 Temperature changes with depth in liquids
and colloids when heated.
261 Factors affecting regulation.
262 Motion of boats through narrow channels.
263 Effect of solvents and papers on performance
of chromatograms.
264 Paper strip in an air stream.
265 Absorption of radiation of heat from a surface.
266 Lead cells.
267 Particle cohesion.
268 Thermopile efficiency.
269 Lecher wires.
270 Formation and bursting of soap bubbles.
271 taking and testing a graphite strip
microphone.
272 Recombination time of ions.
273 A relationship between thermal and electrical
conductivities in metals.
274 Fog lamps.
275 Power transmission efficiency of a cycle
chain.
276 Currents induced in ionic solutions moving
277 Electrical properties in moist gycerol
278 Liquid phase secondary coil in a transformer.
279 The frequency response of dielectric
materials in capacitors.
280 Drainage of a vessel.
281 Penetration effects of air gun pellets on
plasticine and wood.
282 Lubrication of graphite.
283 Efficiency of GM tube.
284 Producing a hologram.
285 Hysteresis in rubber.
286 Elastic properties of fishing line.
287 The flow of water around a U-bend.
288 The transmission reflection and absorption of
ultraviolet light by Polythene.
289 Properties of a paste of flour and water.
290 To investigate the factors affecting the
!strength of a pillar.
291 Analysis of a thermos flask.
292 An investigation into the depth of focus of the
eye.
293 Factors affecting the bow waves produced by
a boat.
294 The effect of turbulation on model glider
aerofoil performance.
295 Factors affecting the playing speeds of a
squash ball.
296 Hot wire windspeed meter.
297 The strength of plaster.
298 Investigating P T F E.
299 Corrosion and cathodic protection.
300 Investigation of Moire fringes as of use in
measuring.
301 Fluid analogue of an electric current.
302 Water shrinkage of tissue paper.
303 The analysis and synthesis of musical
sounds.
304 An investigation of the diffusion of tea through
teabags,
305 The deflection of liquids passing through an
electric field.
306 Torque - r p m curve for a model diesel
engine.
307 Studying the effects of stretching different
plant tissues.
308 Stability of slopes.
309 Linear motor.
310 Hardness of pencils.
311 Humidity switch.
312 Forces on fences.
313 Rupert's drops.
314 Sea anchors.
315 Paramagnetism.
316 The forces between magnets.
317 Is eye colour caused by scattering of light?
318 Solders of various composition.
319 Hysteresis in a transformer.
320 The efficiency of cloud chambers.
321 Factors affecting behaviour of sparks.
322 Motion of elastic pendulum.
323 The effect of reduced pressure upon
ionisation currents in air.
324 Factors affecting the production of uniform
bubble rafts.
325 Rate of deposition of particles from aqueous
suspensions.
326 Measurement of paper thickness.
327 The velocities of selected ions in aqueous
solution.
328 Distribution of velocities of thermoelectrons.
329 The formation of sand dunes.
330 Water flow round obstructions.
331 To construct an accelerometer.
332 Nature of pencil lines.
333 Polarising effects of sellotape.
334 Life history of water drop.
335 Effect of oil on evaporation of liquids.
336 Energy loss in bounces.
337 What causes flapping in flags?
338 Strength of string.
339 Accuracy of hand catapult.
340 Molten metal into water.
341 An investigation into photoelasticity.
342 Resonance of wine glasses,
343 Charge leakage from electroscope.
344 Measurement of speed by Doppler effect.
345 Metals - work hardening and heat treatment.
346 Rings formed by running water on flat plates.
347 Electrode potentials of period 4 transition
metals.
348 Evaluation of chalk/blackboard writing
system.
349 Reverberation time apparatus.
350 Behaviour of ink drops in water.
351 Efficiency of model racing car.
352 Vibrations caused by an electric motor.
353 Electrical resistance welding.
354 Making and calibrating a strain gauge.
355 Diffraction halos produced by small particles.
356 Heat flow through crystals.
357 The effect of twisting on 2 ply wool.
358 Reduction of vibrations subjected upon
equipment.
359 Energy stored/efficiency of a clock.
360 Resonance of metal rings.
361 Production of diffraction gratings.
362 Turbine blades.
363 Refraction of a light beam through unstirred
sugar solution.
364 Construction and use of a chart recorder.
365 Physical properties of hen's eggs.
366 Electrical properties of silver deposited on
glass slides.
367 Millikan's experiment with smoke particles,
368 Measurement of the vapour pressure of water
at various temperatures using microwaves.
369 Feasibility of comparing abrasive
characteristics by light scatter.
370 Application of Bernoulli's principle to design of
chimney pots.
371 Variation of light output and temperature of
tungsten lamps as a function of power input,
372 Effect of electric fields on rate of evaporation
of liquids.
373 Mechanical properties of plastic sulphur.
374 Potential drop method of crack
characterisation.
375 Optimum launching of flying discs.
376 Uniplanor girder design.
377 Apparatus to provide a constant force.
378 Alpha particle absorption by gases.
379 Self inductance of metal springs.
380 The ways in which a glass rod transmits light.