josh siddons- report- unit 3( resub)
TRANSCRIPT
Experiment to determine
acceleration due to gravity using
a Ticker tape method
By
Josh Siddons
17th June 2016
CONTENTS PAGE
Contents
contents page..............................................................................................................................2
PART A: Planning and Background Research ...................................................................4
hypothesis to be tested................................................................................................................................................... 4
Aims and Objectives ........................................................................................................................................................ 4
Limitations of the study ................................................................................................................................................... 4
Background Research and literature review ........................................................................................................... 4
Experimental plan............................................................................................................................................................. 6
Apparatus used............................................................................................................................................................. 6
Diagram of the experimental set up ...................................................................................................................... 7
Figure 1: Set up equipment.................................................................................................................................................... 7
Method with step-by-step instructions .................................................................................................................. 7
Whether repeat readings are required and how anomalies will be handled statistically..................... 8
Details of the graph that will be plotted detailing which variables will be on each axis ....................... 8
Measuring the angle of the ramp............................................................................................................................ 8
Health and Safety ........................................................................................................................................................ 8
Variable types detailing how control variables will be kept the same ........................................................ 9
How precision, accuracy, validity and reliability is addressed within the method.................................. 9
How the graph will be analyzed to obtain a value for ‘g’; and ...................................................................... 9
How sufficient data will be acquired to apply statistical techniques in your analysis ........................... 9
modifications to the Experimental plan ..................................................................................................................... 9
PART B: Results....................................................................................................................10
Description of results and issues noteD during the experiment ..................................................................... 10
Tables of all results (including units and headers).............................................................................................. 10
Table 2: g value results ......................................................................................................................................................... 11
Anomalous Data ............................................................................................................................................................. 11
Table 3: Anomalous data ...................................................................................................................................................... 11
Graphical representation of results .......................................................................................................................... 12
Table 4: Graph to show of acceleration against Sine angle of slope ............................................................................ 12
PART C: Analysis of results and discussion .....................................................................12
Interpretation of gradients of graph and intercepts (if relevant) ..................................................................... 12
statistical Analysis and interpretation ...................................................................................................................... 12
Table 5: Students t-test analysis ................................................................................................................................... 14
Procedural errors ............................................................................................................................................................ 14
Precision errors ............................................................................................................................................................... 15
Table 6: Ticker tape measurement uncertainty .............................................................................................................. 15
Table 7: Measuring height uncertainty .............................................................................................................................. 15
Table 8: Measuring length uncertainty .............................................................................................................................. 16
Table 9: Total uncertainty .................................................................................................................................................... 16
Suggested Improvements............................................................................................................................................ 16
PART D: conclusions ............................................................................................................16
References .............................................................................................................................17
BILBLIOGRAPHY..................................................................................................................18
Appendices.............................................................................................................................18
Table 10: Table of ticker tape results ................................................................................................................................. 21
Table 2: g value results ......................................................................................................................................................... 11
Table 3: Anomalous data ...................................................................................................................................................... 11
Table 4: Graph to show of acceleration against Sine angle of slope ............................................................................ 12
Table 5: Students t-test analysis ......................................................................................................................................... 14
Table 6: Ticker tape measurement uncertainty .............................................................................................................. 15
Table 7: Measuring height uncertainty .............................................................................................................................. 15
Table 8: Measuring length uncertainty .............................................................................................................................. 16
Table 9: Total uncertainty .................................................................................................................................................... 16
Table 10: Table of ticker tape results ................................................................................................................................. 21
PART A: PLANNING AND BACKGROUND RESEARCH
The purpose of the experiment is to see if there is a significant difference between
acceleration due to gravity determined by rolling a trolley down a ramp and working out the
acceleration using ticker tape. This report will present background research on the nature
and value for acceleration gravity along with a range of methods for determining its value.
Furthermore it will present results of the ticker tape experiment which took place and a
conclusion on whether the hypotheses and objectives were met.
HYPOTHESIS TO BE TESTED
There is no significant difference between acceleration due to gravity determined by rolling a
trolley down a slope using ticker tape and comparing it with the value determined using light
gates whilst rolling a trolley down a ramp.
AIMS AND OBJECTIVES
The aims and objectives were:
To find acceleration from the ticker tape and light gates from rolling a trolley down
a ramp.
To compare the value of g from two methods by applying a T-Test.
To evaluate whether my hypotheses should be accepted or rejected from the
results.
LIMITATIONS OF THE STUDY
Limitation of the study were as follows:
At college the level of equipment is at a basic level that is suitable for a student lab
rather than more advanced laboratory work. It is also old and run down over years of
use.
The ramp and trolley which was used was very old, did not have smooth surface
which could off increase the drag.
The space available was limited to a shared classroom environment with other
students other performing experimental work.
Access to college laboratory was limited which limited the time available to carry out
the experiment.
The method required access to a physics teacher in order to help with theory and
equations used.
BACKGROUND RESEARCH AND LITERATURE REVIEW
Definition of gravity:” the force that attracts a body towards the Centre of the earth or
towards any other physical body having mass”- Google
Acceleration of falling objects is due to gravity and this is the same for any object.
Newton’s law of gravitation and relation to “g”
Muncaster (1989) explains newton’s universal law of gravitation as “every particle in the
universe attracts every other with a force which is proportional to the product of their masses
and inversely proportional to the square of their separation”. This is summarised in the
equation below, where F is the gravitational force of attraction between two masses that are
a distance r apart and G is the universal constant of gravitation.
The link between Newton’s law of gravitation and “g” is also described by Muncaster (1989)
who derives the relationship as g = GM/r2 where M is the mass of the earth. This means
that gravity depends on how far away the object is from the centre of the earth.
Factors affecting the value of g at different places on earth
It is not affected by temperature but it does vary at different point on the earth due to
topography. Wikipedia (2015) states that “all small bodies accelerate in a gravitational field
at the same rate relative to the Centre of mass” providing that we ignore the air resistance.
BBC Bitesize (2014) explains that at the top of the mountain the pull of gravity is lower as
you are further away compared to being in valley or at sea level where the gravitational field
strength is much stronger.
Some factors which affect the value of g are:
Mass of the objects: Mass of the objects affects the gravitational forces as the greater the
mass the greater the attractive force between the masses.
Distance between the objects: UCL (n.d.) goes over the idea of the greater the height the
lower the level of g. So if the distance is doubled then the gravity is weaker and the force of
gravity is less than being really close. This shown in the diagram below
Shape of earth: Wikipedia (2016) explains that the shape of the earth
is not an oblate spheroid (looking similar to an American football) it means different points on
the earth’s surface will have feel a greater pull from gravity than others. At the equator where
the bulging of the earth is at its greatest then the pull of gravity is at its weakest. Saxov
(1952) explores this further and describes in more detail a selection of mathematical ways to
work out the level of “g” in different places across the earth.
Methods to determine the value of “g”
Pendulum test: Physics Classroom (n.d.) gives another test for gravity which uses objects
which are hung in midair by a fixed string, which is used for support. This method is based
on mathematical properties of objects that are in periodic or simple harmonic motion.
Muncaster (1989) give s step by step procedure in how to carry out the procedure by
determining the acceleration due to gravity.
Ticker tape: This is method to find out the motion of objects. It works by having marks on the
tape which you would attach to an object along with a piece of string. You would then pull
the string through a device which marks the tape and the dot/marks provide evidence for the
objects motion. Nuffield foundation (2012) gives a detailed procedure clearing explaining
how the procedure work and how you calculate the level of gravity through the test. Physics
Classroom (n.d.) “Ticker tape Diagrams” gives a very clear diagram in how to step the
procedure.
Magnet drop: BBC (2014) describes the method that involves dropping a magnet down the
copper tube hovering down the tube. This could take 30 seconds to travel down 1 m the
compared to it dropping straight way if it was a plastic tube. This is supported by a list
equipment you need, video of the procedure, and what to do if the experiment does not
work.
Linear air track: Physics school (n.d.) present the idea of using an air track to find the level of
g. The way in which the experiment does this is by determining the rate of acceleration of
gravity. Using the air track when carrying out calculations is a positive as there is need to
count for friction. On this sources it gives a diagram of set, a list of what you need along with
a to do list and finally a calculations.
Reasons for method selection
Having considered these methods the ticker tape method was chosen because:
It was very easy to use and set up.
The equipment needed was available in the college
It is possible to produces a large sample size and retake measurements which
reduces the number of uncertainty.
It provide a opportunity to learn to use a the ticker tape machine and analyse ticker
taper data which were techniques that were not known to the investigator.
EXPERIMENTAL PLAN
Apparatus used
1x Ramp
1x Trolley
1x Ticker tape
8x books
1x String ball
1x Spirt level
1x calculator
2x 1m rulers
1x Roll of masking Tape
1x Clamp Stand
2x Wires/cables
2x Clamp & Boss
1x Ruler
Diagram of the experimental set up
Figure 1: Set up equipment
Method with step-by-step instructions
1. Place a thread of string through the trolley.
2. Now create a ramp and note down the angle (How to work it out below), Once
completed place the trolley on the top of the ramp ensuring that all cables have no
bends or knots along and are always stretched.
Start
Ramp
Trolley Clamp & Boss Ticker tape, Connected to power supply
Books 2x 1 Meter ruler
End
3. Turn on the ticker tape to allow it to start vibrating, now remove the ticker tape to
see if the dots are all the same place.
4. Turn off the ticker timer, Now thread a piece of ticker tape through, Attach it to the
trolley and then turn it back on allowing it to vibrate
5. Now let go of the trolley from at the top of the ramp which causes the trolley to roll
down the ramp whilst pulling the ticker tape.
6. Count the first 10 dots and measure the distance.
7. Then on the same tape count another 10 dots and measure, do this 7 times and
note down the results in the table. Repeating it 7 times helps reduce anomalies.
8. Carry this out again but change the height at the top and note the results in the
table.
Whether repeat readings are required and how anomalies will be handled statistically
Noticing anomalies will be seen by noticing if the results are widely wrong (don’t follow the
trend) and how to deal with them is to ignore them when doing the data analyses. Another
way to deal with them would be to do a re-run of the tape to prevent any anomalies.
Details of the graph that will be plotted detailing which variables will be on each axis
Plotting a graph with average speed (M/S) on the X axis and on the Y axis plot cumulative
time (s). To receive the graph you will need to work out the average speed which is
length/time taken. The cumulative time+0.2 each time.
Measuring the angle of the ramp
Trigonometry was use the length to work out angles of slope. Collect two 1M meter sticks
and measure the length of the ramp, note that in a logbook. Then work out the height at
each end of the ramp (Start& End). Use a piece of string to measure the height to help
reduce uncertainties, reducing the zero errors as rulers don't start from zero. Measure the
length of string using a ruler and subtracted the “End” point from away from the “start”. Now
divide the length by the height in the calculator and you will receive an answer. Click shift,
then click Tan and receive Tan-1, Click “ans” and you should have get Tan-1(ans), Click the
“=“button and receive an answer which will be the angle of ramp.
Health and Safety
o Hand or fingers might get in the way of the trolley: Keep your hands out of the
way to prevent your hands/fingers getting hurt.
o Instability of ramp: Ensuring the ramp is secure with no wobble and area
around is tidy.
o Electrical equipment: Turn of any power supply when not in use to help
prevent the risk of any electrical shocks. No overhanging cables.
o The trolley falling off the ramp and hitting the floor: Having someone stand at
the end to catch the trolley or having a stopper to prevent it from falling off.
Variable types detailing how control variables will be kept the same
Independent: Height of Ramp, which altered the angle of slope.
Dependent: Average speed for a standard set of ticker tape (11dots or 10 gaps)
Control: same trolley and constant same start position ramp roll distance.
How precision, accuracy, validity and reliability is addressed within the method
1. When reading the ruler, reading of the mm rather than the cm to give a more
precise reading resulting in the results being more reliable.
2. Measuring the height of the ramp using string instead of a ruler as a ruler does not
start at zero. The further helps in making results more precise and reliable.
3. Reducing the drag of the ticker tape. Ensuring this is applied by ensuring the tape
can roll smoothly, this will give more accurate results meaning the data is going to
be more reliable.
4. Ensuring the ramp was level perpendicular to the roll direction of the trolley. This
will help improve the accuracy.
5. Ensuring that the trolley rolls parallel by drawing a line which it follow’s down the
ramp.
How the graph will be analyzed to obtain a value for ‘g’; and
The graph will be created using “cumulative time” along the x axis and “average speed ”
along the y Axis. Once a graph has been plotted add a trend line, click show equation and
R2 value. From that and the angle measured earlier you will need to work out the (g=a/sin A).
To work this out in the calculator you will need to use the “m” (first number on the gradient
equation) and divide it by sine ((angle/360)*2*PI()).
The final spreadsheet equation should look like =”m” value/Sin ((angle/360)*2*PI()).
The graph helps you get the gradient which then can be used receive the results of the “M”
value which is needed within the final equation.
How sufficient data will be acquired to apply statistical techniques in your analysis
The data which is collected will then be used in a student’s t-test which will compare the
values of g from your test along with the light gate results received. It will allows you to
present the two results along with standard deviation of each to show the comparison.
MODIFICATIONS TO THE EXPERIMENTAL PLAN
Decided not to use the weight to pull the trolley down the ramp.
Reason why is it makes the test simpler to analyses and carry out.
This would increase the level of accuracy as there will be less
variables involves. This will help the results be more accurate as
you will be able to achieve a more precise level g. It will also be
easier to repeat and carry out due to it being more reliable.
Find something to hold the tape to help reduce the level of drag on
the trolley. This will help improve the level accuracy as the results
received will be more accurate. The reason for this will be because
the result it will make the results more valid as there will be less
variable and you will receive a greater true value of g.
PART B: RESULTS
DESCRIPTION OF RESULTS AND ISSUES NOTED DURING THE EXPERIMENT
In summary results obtained using a slope of length 1820mm and slope angles which
ranged from 1.57-5.99 degrees, the acceleration of the trolley down the slope increased
from 0.1134-0.6634 m.s-2. This was calculated using ticker tape sections with 10 spaces of
0.02 seconds (a total time interval of 0.2 seconds), resulting in average velocity values
ranging from 0.430-1.405 m.s-1.
The ticker tapes were easy to collect and were mostly clear and easy to read, although it
was time consuming and detailed work to count each dot and measure the lengths. The
angle of the slope was worked out using trigonometry with the length and height of the
slope. The sine of the slope angle was calculated.
The main issues noted in the experiment were:
• Sometimes reading the dots were very faint which required extra time to reading and count
the dots. However none of the tapes were poor enough to be re-run.
• Regularly the ticker tape was tangled which would add extra drag and increase the effect.
This was solved by ensuring the tape was flat before the trolley was rolled and some re-
runs were needed.
TABLES OF ALL RESULTS (INCLUDING UNITS AND HEADERS)
Details of the measurements collected are presented in the appendices. A summary of the
data used to plot the graph and perform statistical analyse of calculated g values are
presented in table 1.
The table shows:
The sine of the angle of the slope for each ticker tape run,
The acceleration of the trolley down the slope determined using a graphical analyses
of the average velocity of a section of tape plotted against the cumulative time.
The value of g calculated using the equation:
Block sine (angle of
slope)
acceleration (m/s2) from graphs g (m/s2)
2 0.0275 0.1134 8.790
3 0.0412 0.1411 6.536
4 0.0554 0.3313 8.289
5 0.0723 0.4975 8.647
6 0.0876 0.6045 8.364
7 0.0952 0.6564 8.242
8 0.1044 0.6634 7.583
Table 1: g value results
ANOMALOUS DATA
Table 2: Anomalous data
(Reading Number 7)-RED
When dealing with the anomalies ignoring them from the data is the best option. The results
to left show that the 7th data was Igorned and the graph without it. Spotting anomalies is
seeing if the data received is widely wrong and when tested with a line of best fit it’s
nowhere near. Reasons why could be human error when doing the experiment or a random
error may have occurred.
Section Time taken Length(mm) Length (m) Average speed (m/s) cumulative speed (s)
1 0.2 141 0.141 0.705 0.1
2 0.2 154 0.154 0.77 0.3
3 0.2 198 0.198 0.99 0.5
4 0.2 227 0.227 1.135 0.7
5 0.2 259 0.259 1.295 0.9
6 0.2 256 0.256 1.28 1.1
7 0.2 60 0.06 0.3 1.3
Height (mm)
Length (mm)
6.898522347
Average 1.029166667
Standard Deviation 0.252416653
Mean 1.0625
Tan-1(174/1820)= 5.46(2sf)
174
0.6564/sin(5.46)
7 Block
a=g X Sin A
182
g=a/Sin A
y = 0.6564x + 0.6353R² = 0.9468
0
0.375
0.75
1.125
1.5
0 0.35 0.7 1.05 1.4
Series1
GRAPHICAL REPRESENTATION OF RESULTS
Table 3: Graph to show of acceleration against Sine angle of slope
PART C: ANALYSIS OF RESULTS AND DISCUSSION
INTERPRETATION OF GRADIENTS OF GRAPH AND INTERCEPTS (IF
RELEVANT)
The graphs show a positive correlation between the level of acceleration and the angle of
the slope. As the angle of slope increase the greater the acceleration. The graph does not
pass through the origin (0, 0) means the product would not move off as there is no energy
produced to push it off. There are also other factors such as drag on the surface which
prevent the trolley from moving off. The equation gathered from the graph is used to work
out the level of g. The R2 value of 0.97 shows that there is a high correlation as it is very
close to 1. The closer to 1 the higher the level of correlation with 1 being perfect.
STATISTICAL ANALYSIS AND INTERPRETATION
An independent two tailed student’s t-test was performed using two sets of results of data to
assess whether they are significantly different and whether the hypothesis was true. The
ticker tape results (set X) and another student data set collected using the ramp experiment
using light gates (set Y) were used for this analysis. The method used as follows:
Calculate the mean and standard deviation of (X) and (Y)
Calculate the squared values of standard deviation for each sample (these are Sx2
and Sy2 values).
Calculate the standard error (Sxy) from the equation (Sx2/sample size) +
(Sy2/Sample size).
The sample size of both data sets was 7.
Calculate the modulus of the difference of the mean’s | 𝑥̅𝑥 − 𝑥̅𝑦 |.
Calculate the T-statistic (𝑡 =|𝑥 ̅𝑥−𝑥�̅�|
𝑆𝑋𝑌) E.G value you need to divide modulus by the SXY
value = (Modulus/SXY).
Calculate degrees of freedom are then workout by adding the sample size take away
2 (14-2=12).
Used the degrees of freedom to look up critical value from table and t-value the
degrees of freedom to look up in the t-test probability table for the critical value, this
can then be Rejected or accepted.
Table 1 shows this analysis. The hypothesis has to be rejected as the t-value is above the
critical value of 2.18, which means there is a significant difference between the sets of data
at 95% confidence level.
Table 4: Students t-test analysis
PROCEDURAL ERRORS
Things to consider;
Some scatter of points on graph – procedural issues, intercept
How you measured the height of the ramp – affects the calculation of angle of slope. Adjustment for thivkness
of the ramp
Drag of ticker tape, air resistance, friction of trolley on ramp, uneveness – factors that will reduce the
acceleration measured (lower value)
Alignment of ramp and trolley roll
Calibration of ticker tape machine – assuming that each dot is ever 0.02s but could not confirm this.
Will all affect accuracy
Block/Tape Number Ticker Tape Results (X) Light gate Results (Y)
2 8.79 9.28
3 6.54 9.30
4 8.36 9.21
5 8.65 9.32
6 8.29 9.30
7 8.24 9.40
8 7.58 9.21
Mean of ticker tape results (X) 8.064
Mean of light gates (Y) 9.289
Standard Deviation of (X) 0.775
Standard Deviation of (Y) 0.066
Sx2 0.601
Sy2 0.004
Sample size (Nx) 7
Sample size (Ny) 7
Modulus 1.224
Standard Error (Sxy) 0.294
T-statistic 4.162
Degrees of freedom 12
T-test critical value 2.180
Student T-test
The R2 Value of 0.97% shows that there is a high positive correlation but it is not
perfect due to uncertainties such as drag. This in the long run will affect and reduce
the value of “g”
Not always perfectly having the alignment of the ramp and the trolley roll. This would
lead to an increase in friction as it is travelling a longer distance and this will also
affect the value of “g”.
Assuming the ticker tape was calibrated correctly and the dots were 0.02s apart.
This was never tested and would not be able to confirm if it was correct. This would
affect the overall value of “g” as the time could be wrong affecting the distance and
rate of acceleration.
Uneven surface. The surface was very bumpy which increase the level of
resistance and drag. The would further lower the level of value of “g” as there would
be an increase in drag.
PRECISION ERRORS
Measurement uncertainties were calculated for the readings taken, as shown in the tables below. Percentage
uncertainties were calculated using the equation:
% uncertainty =( ½ x Resolution / Actual Reading ) x 100
Ticker tape length
Equation
%U
(Lowest) 86mm (0.5x1)/(86)x100 0.58
(Highest) 281mm (0.5x1)/(281)x100 0.18
Table 5: Ticker tape measurement uncertainty
Tables 2 shows the percentage uncertainties for the shortest and longest ticker tape section
analysed. These were measured using a 30cm ruler which had a resolution to the nearest
mm. (Two 2 figures only)
Height
Equation
%U
50mm (0.5x1)/(50)x100 1.00
101mm (0.5x1)/(101)x100 0.50
132mm (0.5x1)/(132)x100 0.38
174mm (0.5x1)/(174)x100 0.29
191mm (0.5x1)/(191)x100 0.26
Table 6: Measuring height uncertainty
Here shows the percentage uncertainties of the height of the ramp which was measured
using string then the string was measured using a 30cm ruler with a resolution of 1mm. The
highest possible uncertainties are at the lowest height of 50mm with a percentage at 1.000
and the lowest percentage uncertainty is at the highest height with a 0.262.
Length
Equation
%U
1820mm (0.5x1)/(1820)x100 0.28
Table 7: Measuring length uncertainty
This shows the percentage uncertainty of measuring the length of the ramp. I used two 1
meter sticks with smallest resolution of 1mm. The % uncertainty for this is 0.275.
Total %U
3.457
Table 8: Total uncertainty
The Percentage uncertainties for acceleration is the same as percentage uncertainties in the
average speed (figure 5) which will be derived for percentage uncertainty in each ticker tape
section measurement.
Using the data above, the percentage uncertainty for the Sine of angle of slope was found
by adding together the percentage uncertainty for height and length of the slope, as follows:
Worst Case = 1.000(Height) + 0.275(length) =1.275%
Best Case= 0.262(Height) + 0.275(length) = 0.537%
This was then used to determine the (highest) percentage uncertainty due to measurement
instruments used, in determining the value of ‘g’:
% uncertainty in ‘g’ =% uncertainty in acceleration + % uncertainty in sine of slope
=0.581+1.275= 1.856% (approx. 2%)
SUGGESTED IMPROVEMENTS
An improvement which could be made to my Experiment could be having a set place/
run for the ticker tape to flow as when carrying out my experiment there was still drag
which could off affected my results.
Another improvement could be having a smooth running track and trolley. This would
be good as it would reduce drag and help increase the accuracy of the results as the
trolley and ramp which was used was not perfectly smooth and had bumps along the
way.
PART D: CONCLUSIONS
Figure 3 shows the table of the values of g which was received, it shows a range from 6.536-
8.790 and compared to the national accepted level of “g” at 9.811 it is not that far off from
the closest reading.
The experiment which was taken was reliable as the results was repeated at 7 different
height with 7 different read on each height giving you a final total number of reading of 49.
This helps make it reliable due to it being repeatable along with it be more precise and
accurate. This experiment which was carried out was ensured accuracy as the when reading
and measuring the height of the ramp it took in account zero errors such as the lip which
was 20mm high which has to be taken away from the final height. This was shown in the
logbook. Precision was taken into as there was a large amount of data readings there was
also instruments with a finer resolutions such as the meter rulers which was read to the mm
scale.
(Comment about precision uncertainty of 2% being a good value for a school lab
experiment).
The research which was taken out is valid as the research which was carried out as it is
reliable and used the correct physics theory with only having relevant data.
The results from the T-test the hypothesis was rejected due to the final reading being greater
than the critical value of 2.18. This showed that there was no significant difference between
the two pieces of data a confidence level.
All objectives were met as the hypothesis was tested to see if it was accepted or rejected,
there was a comparison between two methods by applying statical values and the level of
acceleration was found from rolling a trolley down a slopes using ticker tape and lights
gates. These are shown in figure 1 and 2.
ADD MORE HERE
REFERENCES
Electronic sources:
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https://en.wikipedia.org/wiki/Gravitational_acceleration(Accessed 19/01/16)
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ml (Accessed 19/01/16)
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19/01/16)
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19/01/16)
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http://www.nuffieldfoundation.org/practical-physics/finding-average-acceleration-ticker-
timer (Accessed 19/01/16)
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http://www.physicsclassroom.com/class/1DKin/Lesson-2/Ticker-Tape-Diagrams (Accessed
19/01/16)
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(Accessed 19/01/16)
E-Book/Books sources:
• Muncaster, R.M.(1989). “Determination of g using a simple pendulum”,pp: 73-74, Stanley
Thorne's
Journal sources:
• Saxov, S (1952), “Variation of gravity within earth”, Danish Geodetic Institute, pp:138-140,
Available at http://onlinelibrary.wiley.com/doi/10.1111/j.2153-3490.1952.tb00998.x/epdf
(Accessed 19/01/16)
BILBLIOGRAPHY
APPENDICES
Block sine (angle of
slope)
acceleration (m/s2) from graphs g (m/s2)
2 0.0275 0.1134 8.790
3 0.0412 0.1411 6.536
4 0.0554 0.3313 8.289
5 0.0723 0.4975 8.647
6 0.0876 0.6045 8.364
7 0.0952 0.6564 8.242
8 0.1044 0.6634 7.583
Table 2:
Table 3:
Table 4:
2 Block
Section Time taken Length(mm) Length (m) Average speed (m/s) Cumulative time (s)
1 0.2 86 0.086 0.43 0.1
2 0.2 89 0.089 0.445 0.3
3 0.2 94 0.094 0.47 0.5
4 0.2 108 0.108 0.54 0.7
5 0.2 112 0.112 0.56 0.9
6 0.2 106 0.106 0.53 1.1
7 0.2 111 0.111 0.555 1.3
3 Block
Section Time taken Length(mm) Length (m) Average speed (m/s) Cumulative time (s)
1 0.2 108 0.108 0.54 0.1
2 0.2 113 0.113 0.565 0.3
3 0.2 128 0.128 0.64 0.5
4 0.2 135 0.135 0.675 0.7
5 0.2 145 0.145 0.725 0.9
6 0.2 155 0.155 0.775 1.1
7 0.2 127 0.127 0.635 1.3
6 Block
Section Time taken Length(mm) Length (m) Average speed (m/s) Cumulative time (s)
1 0.2 112 0.112 0.56 0.1
2 0.2 153 0.153 0.765 0.3
3 0.2 169 0.169 0.845 0.5
4 0.2 192 0.192 0.96 0.7
5 0.2 220 0.22 1.1 0.9
6 0.2 244 0.244 1.22 1.1
7 0.2 260 0.26 1.3 1.3
Table 9: Table of ticker tape results
5 Block
Section Time taken Length(mm) Length (m) Average speed (m/s) Cumulative time (s)
1 0.2 111 0.111 0.555 0.1
2 0.2 139 0.139 0.695 0.3
3 0.2 160 0.16 0.8 0.5
4 0.2 173 0.173 0.865 0.7
5 0.2 197 0.197 0.985 0.9
6 0.2 218 0.218 1.09 1.1
7 0.2 225 0.225 1.125 1.3
4 Block
Section Time taken Length(mm) Length (m) Average speed (m/s) Cumulative time (s)
1 0.2 137 0.137 0.685 0.1
2 0.2 149 0.149 0.745 0.3
3 0.2 162 0.162 0.81 0.5
4 0.2 177 0.177 0.885 0.7
5 0.2 196 0.196 0.98 0.9
6 0.2 208 0.208 1.04 1.1
7 0.2 210 0.21 1.05 1.3
7 Block
Section Time taken Length(mm) Length (m) Average speed (m/s) Cumulative time (s)
1 0.2 141 0.141 0.705 0.1
2 0.2 154 0.154 0.77 0.3
3 0.2 198 0.198 0.99 0.5
4 0.2 227 0.227 1.135 0.7
5 0.2 259 0.259 1.295 0.9
6 0.2 256 0.256 1.28 1.1
7 0.2 60 0.06 0.3 1.3
8 Block
Section Time taken Length(mm) Length (m) Average speed (m/s) Cumulative time (s)
1 0.2 103 0.103 0.515 0.1
2 0.2 136 0.136 0.68 0.3
3 0.2 199 0.199 0.995 0.5
4 0.2 198 0.198 0.99 0.7
5 0.2 224 0.224 1.12 0.9
6 0.2 228 0.228 1.14 1.1
7 0.2 281 0.281 1.405 1.3