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Transcript
EEI – RESISTANCE OF
GRAPHITE: JOURNAL
Figure 1 - http://tinypencil.com/main/wp-content/uploads/2013/01/Graphite-schist.jpg
By: Jackson Best
EXPERIMENT DATE: 24 NOVEMBER 2014
Page 0 of 18
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
Table of Contents:
TABLE OF CONTENTS: ______________________________________________________________________ 1
AIM: ____________________________________________________________________________________ 2
QUESTIONS, THOUGHTS AND MYSTERIES:______________________________________________________ 2
IDEAS FOR EXPERIMENT - METHOD OF TESTING: ________________________________________________ 2
RESEARCH, PLANNING AND BACKGROUND: ____________________________________________________ 2
WHAT IS GRAPHITE: BASICS ____________________________________________________________________ 2
CHEMICAL AND ADVANCED PROPERTIES OF GRAPHITE: _________________________________________________ 3
ELECTRONICS: ____________________________________________________________________________ 3
OTHER/GENERAL SCIENCE:____________________________________________________________________ 5
FINAL HYPOTHESIS: ________________________________________________________________________ 5
DEVELOPMENT OF PROCEDURES:_____________________________________________________________ 5
PUT ELECTRICITY THROUGH GRAPHITE POWDER: ______________________________________________________ 5
PUT ELECTRICITY THROUGH GRAPHITE PENCIL: _______________________________________________________ 5
PUT ELECTRICITY THROUGH GRAPHITE PACER LEAD: ____________________________________________________ 5
PUT ELECTRICITY THROUGH GRAPHITE BAR: _________________________________________________________ 6
CHOSEN METHOD OF TESTING: ______________________________________________________________ 6
PUT ELECTRICITY THROUGH GRAPHITE PACER LEAD:____________________________________________________ 6
EQUIPMENT REQUIRED: ____________________________________________________________________ 6
MATERIALS:______________________________________________________________________________ 6
RISK ASSESSMENT: ________________________________________________________________________ 7
METHOD: ________________________________________________________________________________ 9
RESULTS AND DATA: ______________________________________________________________________ 10
RESULTS GRAPHS: _________________________________________________________________________ 12
DATA ANALYSIS: _________________________________________________________________________ 14
QUESTIONS FROM BEGINNING OF JOURNAL: _______________________________________________________ 14
EXPERIMENT ANALYSIS: _____________________________________________________________________ 15
GOD’S DESIGN: __________________________________________________________________________ 16
CONCLUSION: ___________________________________________________________________________ 16
RECORD OF ACTIVITIES:____________________________________________________________________ 17
20 OCTOBER 2014: _______________________________________________________________________ 17
24 OCTOBER 2014: _______________________________________________________________________ 17
28 OCTOBER 2014: _______________________________________________________________________ 17
30 OCTOBER 2014  1 NOVEMBER 2014: _______________________________________________________ 17
2 NOVEMBER 2014: _______________________________________________________________________ 17
3 NOVEMBER 2014: _______________________________________________________________________ 17
BIBLIOGRAPHY: __________________________________________________________________________ 18
WEBSITES:______________________________________________________________________________ 18
PICTURES: ______________________________________________________________________________ 18
Page 1 of 18
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
Aim:
To investigate the electrical properties of graphite, in particular the changing resistance of the
material.
Questions, Thoughts and Mysteries:
Is the change in resistance linear non-linear?
My answer: Do not know
Why does the resistance change?
My answer: the current flowing through it causes a change in molecular structure
At what voltage will a graphite rod light on fire or burn out like a fuse?
My answer: around 5 volts
Graphite is not a metal. Why does it conduct electricity?
My answer: it must have free electrons
Ideas for Experiment - Method of Testing:
Put electricity through graphite powder
Put electricity through graphite pencil
Put electricity through graphite pacer lead
Put electricity through graphite bar
Research, Planning and Background:
What is graphite: basics
What’s it made of?
Figure 2 -
http://www.troelsgravesen.dk/graphite_file
Graphite is a mineral made “exclusively of the
s/graphite_6.jpg
element carbon” (Friedman, Minerals.net, 2014).
Diamond is also made up exclusively the same
element. Even though graphite and diamond are made up of the same element, they have very
contrasting properties. Diamond is hard and very difficult to break. Graphite is extremely easy to
break, is very soft and rubs off onto other objects very easily.
Where is it found?
Graphite is a very common material. Graphite mines “produce enormous quantities [of graphite]
from a single or several large graphite veins” but good quality graphite crystals are very uncommon
(Friedman, Minerals.net, 2014). Graphite is a metamorphic rock meaning that it is formed through
heat and pressure which occurs deep underground.
Page 2 of 18
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
Chemical and Advanced Properties of Graphite:
Molecular Structure and Properties:
Graphite “consists of many flat layers of hexagons” with each layer called a “graphene sheet”
(France, GCSE Science, 2014). The hexagonal structure means that each carbon atom in the molecule
is connected to “three other carbon atoms” (France, GCSE Science, 2014).
Carbon is a member of the fourth group of the periodic table meaning that it has “four electrons in
its outer shell” (France, GCSE Science, 2014). Due to the structure of the molecule, only three of the
four electrons are used for bonding and the other electron is a free electron. This free electron is
what allows graphite to conduct electricity.
The graphene sheets are not strongly bonded together. This means that each layer is easily able to
slide over one another. This is what allows the graphite to rub onto other materials so easily. It also
causes graphite to be very slippery and this makes it a good lubricant.
How is it used?
Due to the widespread and diverse properties of graphite, it has many uses. It is considered a “key,
strategic material” in the new age of technology (Focus Graphite Inc., 2014). It is used in fields. Due
to the way that graphene sheets are able to slide over each other so easily allows it to be used in
several lubricating applications. This property also reveals why the material rubs off onto other
materials so easily. This makes graphite a prime ingredient for the lead inside our everyday pencils.
Graphite’s conductive properties have also caused a large impact on electronics with a natural, nonmetal material being used to run devices such as phones and laptops.
Graphite and electronics:
Graphite’s bonding pattern causes it to have one free electron per carbon atom left in the molecule.
These free electrons allow electricity to flow through the molecule quite easily. Unlike all other
materials, graphite is the “only common non-metal that is a good conductor of electricity”
(Friedman, Minerals.net, 2014). This makes graphite very unique amongst other common, non-metal
materials.
Just like all materials, graphite has a resistance to the flow of electrical current. Unlike other
materials, however, as the voltage through the material increases, the graphite undergoes a process
called “resistivity relaxation” (Wiley, Wiley Online Library, 2014). This process occurs in “highdensity” materials such as graphite (Wiley, Wiley Online Library, 2014). The process describes a
change in the resistance of the given material where, as the voltage through the material increases,
the resistance of the material decreases.
Electronics:
Voltage:
Voltage is a “measure of the energy per coulomb of charge”
in an electrical circuit (Pearson, p371, 2007). It is also
referred to as the electromotive force – EMF (Pearson,
p371, 2007). Voltage can be seen as water in a tank above
the ground. The voltage can be seen as the amount of energy per litre of the water which depends
on the height of the water above the ground. Voltage is also the potential difference between two
points. It is the work required to move a charge between
Figure 3 the two points (Pearson, p371, 2007). Voltage is measured
http://www.ardenelectronics.com/images/circ
in Volts or J/C (Joules per Coulomb).
uit.jpg
Page 3 of 18
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
Current:
The current of a circuit is the speed at which coulombs of charge travel and is measured in amperes
(A). It is the “number of coulombs of charge passing a point each second” (Pearson, p371, 2007).
Therefore, 1 ampere is equal to 1 coulomb per second. Conventional current flows from positive to
negative (Pearson, p371, 2007). This does not represent the actual movement of particles but rather
is just a historical convention. In metals, for example, “the electrons move from negative to positive”
(Pearson, p371, 2007).
Ammeter:
Current can be measured by using an ammeter (Pearson, p371, 2007). When measuring the current
of a circuit, the ammeter is placed “in series with the component through which the current is to be
measured” (Pearson, p371, 2007). An ammeter is designed with an extremely low resistance so that
the full current flowing through the circuit can be measured (Pearson, p371, 2007).
Resistance:
A resistor is anything that “impedes the flow of current” (Pearson, p372, 2007). It can be likened to a
tap on a water tank which slows the flow of the water from the tank. The total resistance of resistors
wired in series is larger than the resistance of each component. The total resistance of resistors
wired in series is equal to “the sum of the individual resistances” (Pearson, p372, 2007). When wired
in parallel, the total resistance is able to be calculated by: “
1
𝑅𝑇
=
1
𝑅1
+
1
𝑅2
+
1
𝑅3
+ ⋯+
1
” where
𝑅𝑘
Rk is
the resistance of the last resistor in the parallel circuit (Pearson, p372, 2007). Resistance is measured
in ohms (Ω). Due to the resistor slowing the flow of the current, some of the energy is released
through heat or other forms of energy.
Ohm’s Law:
The current and voltage in a circuit are related in
accordance with the resistance of the circuit. The
relationship between the voltage, current and the
resistance of a circuit can be “demonstrated by
Ohm’s Law”: “𝑉 = 𝐼𝑅” (Pearson, p373, 2007). Using
this law, it can be seen that, providing the voltage
remains constant, as the resistance increases, the
amount of current through the circuit decreases.
Figure 4 http://images.tmcnet.com/tmc/misc/articles/Image/20
12/electricity.jpg
Page 4 of 18
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
Other/General Science:
Precision, Uncertainty and Accuracy:
Precision and uncertainty is a part of all experiments. Precision is a measure of the reproducibility of
a measurement. “The more variation between successive measurements of the same quantity, the
less precise is the measurement” (Greg Strahorn, Atomic Theory and Precision in Physics, 2014). The
precision of a reading is often shown by the number of significant figures in the measurement.
“Uncertainty refers to human judgement involved in a measurement” (Greg Strahorn, Atomic Theory
and Precision in Physics, 2014). Usually, the uncertainty is taken as ± half the smallest division of the
measuring instrument. When multiple quantities with uncertainty are combined, the uncertainties
have to be recalculated as well. When adding or subtracting values, the absolute uncertainties –
uncertainties as a number – are added. When multiplying or dividing quantities, the relative
uncertainties – uncertainties as a percent of the quantities that they apply to – are added. The
calculations of uncertainties allow people to understand how accurate and precise a value is.
The accuracy of a value is very important and there are many sources of error that can affect this.
The accuracy of a quantity is “an indication of how close a measurement is to the accepted value of
the quantity being measured” (Greg Strahorn, Atomic Theory and Precision in Physics, 2014).
Sources of error include random error - occurs as a result of incorrect reading and effects such as the
parallax effect; systematic errors – errors caused by incorrect calibration of a measuring instrument
(these errors occur in a consistent way – an instrument not reading zero when it should). These
types of errors can effect measurements and should be considered when recording results.
Final Hypothesis:
The resistance will decrease in a non-linear relationship with the voltage that is put through the
graphite.
Development of Procedures:
Put electricity through graphite powder:
Use a power supply to put current through graphite powder and analysing the changes in resistance.
Problem: Graphite powder is hard to use accurately without making a mess.
Put electricity through graphite pencil:
Use a power supply to put current through graphite pencil and analysing the changes in resistance.
Problem: This method could light the pencil on fire do to the heat that the graphite could produce.
Put electricity through graphite pacer lead:
Use a power supply to put current through graphite powder and analysing the changes in resistance.
This is a good idea because the material was graphite and
nothing else that could catch fire. The material would also hold
its physical form allowing electrodes to be easily attached to
either ends of the material. Observations would be easy to make
due to the open view of the graphite pace lead unlike the pencil
where the graphite would be covered in wood or alternative
covering.
Page 5 of 18
Figure 5 http://officemetro.com.au/images/medi
um_14899.jpg
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
Put electricity through Graphite bar:
No graphite bars were readily available for use. If graphite bars were used, any damage done to
them due to heat would be more costly as well as more dangerous.
Chosen Method of Testing:
Put electricity through Graphite pacer
lead:
Use a power supply to put current through
graphite powder and analysing the changes
in resistance.
This is a good idea because the material was
graphite and nothing else that could catch
fire. The material would also hold its
Figure 6 - Experiment - 24 October 2014
physical form allowing electrodes to be
easily attached to either ends of the material.
Observations would be easy to make due to the open view of the graphite pace lead unlike the
pencil where the graphite would be covered in wood or alternative covering.
Equipment Required:
Materials:




Wires
Digital Power Supply
Graphite pencil or graphite rod
Multimeter or:
o Ammeter
Figure 7 - Experiment - 24 October 2014
Figure 8 - Experiment - 24 October 2014
Page 6 of 18
Resistance of Graphite
By: Jackson Best
Risk Assessment:
Page 7 of 18
Teacher: Mr Strahorn
Resistance of Graphite
By: Jackson Best
Page 8 of 18
Teacher: Mr Strahorn
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
Method:
1. Attach power supply to either ends
of the graphite rod
2. Set the power supply to 1.0 volts
with over-current protection
switched on and set to a suitable
amount
3. Switch on the power supply
4. Record the current going through
the graphite
Figure 9 - Experiment - 24 October 2014
5. Increase the voltage by 0.1 volts
6. Repeat steps 4 and 5 until the voltage reaches 3.0 Volts or until graphite burns out
Note: Graphite will burn out and break like a fuse if current becomes too high
Page 9 of 18
Results and Data:
Results Table:
Trial
#
Voltage
Voltage
Precision
Voltage
Relative
Current
Current
Precision
Current
Relative
(Independent)
Absolute
Precision
(Dependant)
Absolute
Precision
Resistance
Resistance
Relative
Resistance
Precision
Precision
Absolute
1
0.000 V
±0.0005
±0.0000%
0.007 A
±.0005
±7.1429%
0.000 Ω
±7.1429%
±0.0000000
2
0.100 V
±0.0005
±0.5000%
0.073 A
±.0005
±0.6849%
1.370 Ω
±1.1849%
±0.0162319
3
0.200 V
±0.0005
±0.2500%
0.139 A
±.0005
±0.3597%
1.439 Ω
±0.6097%
±0.0087728
4
0.300 V
±0.0005
±0.1667%
0.206 A
±.0005
±0.2427%
1.456 Ω
±0.4094%
±0.0059619
5
0.400 V
±0.0005
±0.1250%
0.270 A
±.0005
±0.1852%
1.481 Ω
±0.3102%
±0.0045953
6
0.500 V
±0.0005
±0.1000%
0.337 A
±.0005
±0.1484%
1.484 Ω
±0.2484%
±0.0036850
7
0.600 V
±0.0005
±0.0833%
0.405 A
±.0005
±0.1235%
1.481 Ω
±0.2068%
±0.0030636
8
0.700 V
±0.0005
±0.0714%
0.478 A
±.0005
±0.1046%
1.464 Ω
±0.1760%
±0.0025779
9
0.800 V
±0.0005
±0.0625%
0.546 A
±.0005
±0.0916%
1.465 Ω
±0.1541%
±0.0022575
10
0.900 V
±0.0005
±0.0556%
0.624 A
±.0005
±0.0801%
1.442 Ω
±0.1357%
±0.0019570
11
1.000 V
±0.0005
±0.0500%
0.696 A
±.0005
±0.0718%
1.437 Ω
±0.1218%
±0.0017506
12
1.100 V
±0.0005
±0.0455%
0.771 A
±.0005
±0.0649%
1.427 Ω
±0.1103%
±0.0015737
13
1.200 V
±0.0005
±0.0417%
0.861 A
±.0005
±0.0581%
1.394 Ω
±0.0997%
±0.0013901
14
1.300 V
±0.0005
±0.0385%
0.953 A
±.0005
±0.0525%
1.364 Ω
±0.0909%
±0.0012404
15
1.400 V
±0.0005
±0.0357%
1.023 A
±.0005
±0.0489%
1.369 Ω
±0.0846%
±0.0011576
16
1.500 V
±0.0005
±0.0333%
1.115 A
±.0005
±0.0448%
1.345 Ω
±0.0782%
±0.0010517
17
1.600 V
±0.0005
±0.0313%
1.219 A
±.0005
±0.0410%
1.313 Ω
±0.0723%
±0.0009485
18
1.700 V
±0.0005
±0.0294%
1.317 A
±.0005
±0.0380%
1.291 Ω
±0.0674%
±0.0008697
19
1.800 V
±0.0005
±0.0278%
1.395 A
±.0005
±0.0358%
1.290 Ω
±0.0636%
±0.0008209
20
1.900 V
±0.0005
±0.0263%
1.526 A
±.0005
±0.0328%
1.245 Ω
±0.0591%
±0.0007356
21
2.000 V
±0.0005
±0.0250%
1.623 A
±.0005
±0.0308%
1.232 Ω
±0.0558%
±0.0006877
Page 10 of 18
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
22
2.100 V
±0.0005
±0.0238%
1.700 A
±.0005
±0.0294%
1.235 Ω
±0.0532%
±0.0006574
23
2.200 V
±0.0005
±0.0227%
1.814 A
±.0005
±0.0276%
1.213 Ω
±0.0503%
±0.0006099
24
2.300 V
±0.0005
±0.0217%
1.929 A
±.0005
±0.0259%
1.192 Ω
±0.0477%
±0.0005683
25
2.400 V
±0.0005
±0.0208%
2.039 A
±.0005
±0.0245%
1.177 Ω
±0.0454%
±0.0005339
26
2.500 V
±0.0005
±0.0200%
2.135 A
±.0005
±0.0234%
1.171 Ω
±0.0434%
±0.0005084
27
2.600 V
±0.0005
±0.0192%
2.278 A
±.0005
±0.0219%
1.141 Ω
±0.0412%
±0.0004700
28
2.700 V
±0.0005
±0.0185%
2.370 A
±.0005
±0.0211%
1.139 Ω
±0.0396%
±0.0004513
29
2.800 V
±0.0005
±0.0179%
2.505 A
±.0005
±0.0200%
1.118 Ω
±0.0378%
±0.0004227
30
2.900 V
±0.0005
±0.0172%
2.612 A
±.0005
±0.0191%
1.110 Ω
±0.0364%
±0.0004040
31
3.000 V
±0.0005
±0.0167%
2.677 A
±.0005
±0.0187%
1.121 Ω
±0.0353%
±0.0003961
Page 11 of 18
Results Graphs:
Resistance of Graphite
1.600
1.400
Resistance (Ohms)
1.200
1.000
0.800
0.600
0.400
0.200
0.000
Voltage (Volts)
Page 12 of 18
Voltage vs. Current
3
2.5
Current (Amps)
2
1.5
1
0.5
0
-0.5
Voltage (Volts)
Page 13 of 18
Data Analysis:
Questions from Beginning of Journal:
Does the resistance of the graphite change?
By examining both of the results graphs, it is obvious that the resistance of the graphite does not
remain constant. The “Resistance of Graphite” graph shows this change in resistance for each
voltage setting. When examining the “Voltage vs. Current” graph, it can be seen that the relationship
is not linear. If the line of the graph was linear, the resistance of the graphite would be constant.
However, because it is a curved, non-linear line, it is evident that the voltage changes.
Why does the resistance change?
As seen in the research section, as current is put through the graphite, it undergoes a process called
resistivity relaxation. This lowers the resistance of the graphite as more voltage is put through it. This
process occurred in the experiment and was observed by analysing the data graph. It was seen that
the resistance of the graphite pacer lead decreased as more voltage was put through it. The current
through the graphite pacer lead also increased in accordance with the change in resistance and the
increase in voltage.
Is the change in resistance non-linear?
By examining the “Resistance of Graphite” graph, it can be assumed that the change in the
resistance of the graphite is linear. The graph did contain a large amount of noise and this cause the
data to not be smooth. If a more accurate ammeter was used, smoother data could have been
recorded. This would allow better examination of the data so as to observe wether the change in
resistance of graphite is linear or non-linear.
At what voltage will a graphite rod light on fire or burn out like a fuse?
As the voltage through the graphite pacer lead increased, the graphite pacer lead became hotter to
the point where it began to produce a small amount of smoke. This occurred at 2.3 volts. The voltage
was increased further to 2.7 volts, where it
began to glow red. The voltage through the
graphite pacer lead was then increased to 3
volts. At this point, the graphite pacer lead
produced a large amount of smoke and then
proceeded to burn out like a fuse from the high
amount of current travelling through it. It was
evident that a total current of 2.677 Amps
flowing through the graphite pacer lead would
cause it to “burn out”.
Figure 10 - Experiment - 24 October 2014
Graphite is not a metal. Why does it conduct
electricity?
The way that carbon atoms bond in graphite molecules leave one of the carbon atom’s electrons
“free”. This leaves one free electron per carbon atom floating through the molecule. These “free”
electrons are able to interact with external charges and this allows the graphite molecule to conduct
electricity. These properties make the graphite molecule unique amongst other non-metal molecules
due to its capability to conduct electricity.
Page 14 of 18
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
Experiment Analysis:
What went well?
The graphite pacer lead was attached to the connecting wires in open view of the observers. This
allowed good observation of the visual changes occurring in the graphite pacer lead. As the graphite
pacer lead heated up due to the increase in the current flowing through it, it began to glow red. Due
to the open view of the experiment, the red glow was easily seen and observed as both a piece of
data and a safety hazard.
Due to adequate and extra safety measures being put into place, the voltage through the graphite
pacer lead was able to be increased so that the temperature increased to the point where the
graphite pacer lead burnt out like a fuse and disintegrated in the middle. As opposed to simply
increasing the voltage in an open environment, the system was placed in a safe and protective box
so that, if any fire was to occur, the system could be isolated and no fire could spread outside the
box.
The digital power supply used on the
experiment was very accurate and easy to use.
As a part of its features, it contained an
ammeter. This ammeter was quite accurate
and read four digits thus providing three
decimal places. This built-in ammeter removed
the need for an external ammeter and lowered
the amount of “clutter” in the experiment.
What did not go well?
Figure 11 http://www.ardenelectronics.com/images/circuit.jpg
Due to the diameter of the graphite pacer leads
being only 0.7 millimetres, they broke very easily. This caused some difficulty while setting up the
experiment. In order to complete the experiment with a whole, unbroken graphite pacer lead, care
was taken during all steps. The issue could have also been remedied by using a graphite rod of larger
diameter. This would have increased the strength of the rod and made the experiment easier.
Due to the fragile nature of the graphite pacer lead, it was difficult to establish an organised setup
for the circuit. Instead of attempting to secure the graphite pacer leads and the connecting wires to
retort stands, the wires were left to coil naturally on the bench. This meant that little force was
exerted on the graphite pacer lead by the wires. This gave the graphite pacer lead the best likelihood
of not snapping during the experiment. This somewhat unprofessional setup of the experiment may
also have caused some inconsistencies in the data read from the ammeter. Between different
voltages, slight movements in the wires could have changed the connection and thus changed the
effectiveness of the connection.
As can be seen in the results graph, there was a moderate amount of “noise” in the data. There are
many factors that can cause noise in an experiment. For this experiment, these factors may have
included things such as magnetic fields in the surrounding area as well as electric fields in the air
around the experiment. Because the experiment was not conducted in a fully isolated area,
magnetic fields in the area around the experiment would have been able to affect the experiment in
many ways thus changing the reading from the ammeter. Electric fields in the air around the
experiment may also have affected the experiment by interacting with the current flowing through
the connecting wires and through the graphite pacer lead.
Page 15 of 18
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
Sources of Error:
Sources of error in the experiment included many factors. These included external interferences and
the lack of a large load in the circuit. The readings given by the ammeter could have been affected
by external magnetic and electric fields in the air and the objects surrounding the experiment. The
readings may have also been influenced by the lack of a large load in the circuit. Placing a load into
the circuit would have better simulated a real circuit by not have so much current flowing through
the graphite. This would have reduced the noise in the results and produced better, more consistent
results.
How could the experiment be improved to obtain better results?
In order to remove some of the sources of error, the experiment could be improved in many ways. In
order to obtain more accurate readings, the current running through the circuit could be measured
by an external ammeter. This would most likely provide better readings and therefore smoother
data. Due to the burning out of the graphite, it was impossible to test voltages higher than 3.0 volts.
In order to rectify this, the graphite pacer lead could be connected and placed into a cold, nonconducting liquid or an alternate cooling system. The rod would then be left to cool between each
trial so that for each voltage that it is tested for, it would start at the same temperature. This would
provide more consistent data by removing the factor of the starting temperature between trials.
Some of the “noise” in the data was created from slight movements of the connections in the circuit.
This issue could be fixed by using a rigid structure to mount and hold the wires and the graphite
pacer lead so that they did not move during the trials. This would prevent the connections from
moving and thus remove “noise” from the data.
God’s Design:
Graphite is a very complex and interesting compound. With His
wisdom, God has given us a fantastic mineral that has some
amazing properties. God has also given graphite many uses in
our world such as in stationery equipment, lubricants and
electronics. It is a fantastic compound which really
demonstrates the brilliance of God’s design.
Conclusion:
Figure 12 -
http://cdn.onextrapixel.com/wpDuring the experiment, the electrical properties of graphite
content/uploads/2012/01/25-inspiringwere observed via the use of a graphite pacer lead. The
hands-gods-hand.jpg
experiment provided some new knowledge into God’s fantastic
design of graphite, the understanding of the changing
resistance of the mineral and how graphite can be used in today’s world of electricity.
Page 16 of 18
Resistance of Graphite
By: Jackson Best
Record of activities:
20 October 2014:

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Chose EEI topic: Resistance of Graphite
Began work on report
o Introduction
o Materials
o Results – preparation
o Hypothesis
o Aim
24 October 2014:

Continued work on report
o More introduction
o Method
o Did experiment
o Got results and put them in table
28 October 2014:

Worked on results
o Formatted results into excel
o Used excel equation to calculate resistance
o Graphed resistance against voltage
30 October 2014  1 November 2014:

Worked on journal
2 November 2014:


Worked on journal
Worked on presentation
3 November 2014:

Worked on presentation
Page 17 of 18
Teacher: Mr Strahorn
Resistance of Graphite
By: Jackson Best
Teacher: Mr Strahorn
Bibliography:
Websites:

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David Madden (ed.al), Physics, A Contextual Approach – second edition, Heinemann ,
Port Melbourne, Victoria, Australia
Greg Strahorn, 2014, Atomic Theory and Precision in Physics,
o (See attached – or included in folder)
Hershal Friedman, Minerals.net, 2014
o http://www.minerals.net/mineral/graphite.aspx
Dr Colin France, GCSE Science, 2014, United Kingdom
o http://www.gcsescience.com/a34-structure-graphite-giant-molecule.htm
Focus Graphite Inc., 2014, Ottawa, Ontario,
o http://www.focusgraphite.com/technology/graphite/
John Wiley, Wiley Online Library, John Wiley and Sons Inc., 2014
o http://onlinelibrary.wiley.com/doi/10.1002/polb.21111/abstract
Pictures:

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http://tinypencil.com/main/wp-content/uploads/2013/01/Graphite-schist.jpg
http://chewtychem.wiki.hci.edu.sg/file/view/graphite.jpg/213112794/390x423/graphite
.jpg
http://officemetro.com.au/images/medium_14899.jpg
http://images.tmcnet.com/tmc/misc/articles/Image/2012/electricity.jpg
http://www.troelsgravesen.dk/graphite_files/graphite_6.jpg
http://www.professionalresumewriters.net/wp-content/uploads/2014/07/Danger.png
http://i.ytimg.com/vi/BwKQ9Idq9FM/maxresdefault.jpg
http://cdn.onextrapixel.com/wp-content/uploads/2012/01/25-inspiring-hands-godshand.jpg
http://www.ardenelectronics.com/images/circuit.jpg
Page 18 of 18