• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10
  11. 11
    11
  12. 12
    12
  13. 13
    13
  14. 14
    14
  15. 15
    15
  16. 16
    16
  17. 17
    17
  18. 18
    18
  19. 19
    19
  20. 20
    20
  21. 21
    21
  22. 22
    22
  23. 23
    23
  24. 24
    24
  25. 25
    25
  26. 26
    26
  27. 27
    27
  28. 28
    28
  29. 29
    29
  30. 30
    30

Carbon track experiment

Extracts from this document...

Introduction

Luke Johnston

Physics Coursework - Carbon Track Experiment

Aim: To investigate if the resistance of a carbon track is proportional to its length and width.

Introduction: Carbon has interesting properties and this is why I am investigating it as it is a very important element in electronics. It is a semi-conductor, which is why carbon is very interesting, which means that it behaves like an insulator when cold, but when warm it becomes poor conductors. Carbon is a form of graphite, which I will be using to investigate. Graphite is unusual because it is a non-metal which conducts and is the only non-metal pure element that conducts electricity which makes it useful in electronic circuits.

Theory:

Resistance (considered in this experiment) is the slowing of a current through the carbon track. This means that the carbon track is a conductor. A conductor is an element which allows electricity or heat through their electrons. The more free electrons elements have, the more that element can conduct.

The electricity gives the free electrons a charge and so they begin to move randomly and crash into other free electrons. This happens all along the length of the conductor and so the electrons begin to move from the negative connection to the positive connection (this happens because electrons are negatively charged). Resistance is caused by these free charged electrons crashing into fixed particles (nuclei and protons), other free electrons and particles.

...read more.

Middle

Average (Ω)

1.0

3.43

3.32

2.94

3.23

3.0

6.93

7.07

7.11

7.04

5.0

10.93

12.96

10.70

11.53

7.0

12.78

17.18

17.82

15.93

9.0

15.44

20.30

21.45

19.06

11.0

18.53

24.49

22.64

21.89

13.0

22.11

26.96

26.01

25.03

15.0

27.22

29.05

29.67

28.65

17.0

30.90

32.43

33.46

32.26

19.0

34.84

37.19

34.90

35.64

21.0

37.33

39.56

38.77

38.55


image01.png


Width (cm)

Test 1 (Ω)

Test 2 (Ω)

Test 3 (Ω)

Average (Ω)

10.0

9.7

12.7

10.9

11.1

9.0

5.7

5.5

5.4

5.5

8.0

4.8

4.7

4.8

4.76

7.0

4.3

4.5

4.6

4.47

6.0

3.7

3.5

3.5

3.57

5.0

3.3

3.1

3.1

3.17

4.0

3.0

2.9

3.0

2.97

3.0

2.6

2.7

2.7

2.67

2.0

2.2

2.6

2.1

2.3

1.0

1.9

1.8

1.9

1.87


image05.png


Width (cm)

1/width (cm)

Resistance (Ω)

1.0

1.000

1.87

2.0

0.500

2.30

3.0

0.333

2.67

4.0

0.250

2.97

5.0

0.200

3.17

6.0

0.167

3.57

7.0

0.143

4.47

8.0

0.125

4.76

9.0

0.111

5.50

10.0

0.100

11.10

The reciprocal of width against resistance (1/width)


image06.png


Results 2

Length (cm)

Test 1 (Ω)

Test 2 (Ω)

Test 3 (Ω)

...read more.

Conclusion

Width

Once again, results 2 shows the most resistance due to the facts mentioned in the Length section. This is closely followed by results 1 which shows that there is not much difference in resistance in the widths of results 1 and 2 which may contradict my theory a bi, of the thickness of the carbon track affecting the resistance, but still shows that this does have an affect. In other words, the thickness of the carbon track does not have as much affect on the resistance in the width, whereas it does on the length. Again, the large copper has the lowest resistance.

Reciprocal

This basically shows the same theories as in the topic of Length just discussed above. The results 2 have the highest resistance, and then followed closely by results 1, and then the lowest, by far is the large copper.

My results show that the copper hoops were the right choice as they were easier to take readings down whereas the large copper was hard to take readings as they were so small.

Evaluation

There were anomalies in my results, mainly the large copper as it was all basically an anomalous result as it was very difficult to take the right readings. To overcome this I could have lowered the reading measurement

                                                                                                                            Page

...read more.

This student written piece of work is one of many that can be found in our GCSE Electricity and Magnetism section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Electricity and Magnetism essays

  1. How does length and width affect resistance

    put the wire connected to the ammeter on the wire at 100cm 4. Switch on the plug for the variable dc power pack. 5. Put it on 6 volts on the dial. 6. One person should read out the values and the voltmeter and ammeter and the other should record it neatly on a table.

  2. Design an experiment to predict and test the output from a simple AC generator.

    As is shown above there are 6 viable options for the generator combination. Bulb 4 with wires 3, 4, 5 and 6 and bulb 5 with wires 3 and 4. However some combinations use less but the wire is more expensive whereas some combinations use more wire but it is cheaper.

  1. Find out how the length and width affect the resistance of a graphite track.

    It is also useful to know about the resistance of carbon to understand the principles of a potentiometer (a resistance producing piece of apparatus). In previous experiments I have looked at the electrical resistance of different types of metal including copper and constantine.

  2. An Investigation into how the resistance of a piece of graphite paper is affected ...

    To prove my find I did the same experiment for 28cm and for both the preliminary experiment and the repeat the reading on the ammeter came out to be higher than 1mA (near to full-scale deflection). Hence I can't use it as my length and so I will use 29cm.

  1. Resistance of Carbon Putty.

    The putty was capable of reaching high temperatures when a large current was run through it, I made sure that the putty was cool enough to handle after contact with electricity. 6. We were given a knife to cut the putty with, we handled this with care.

  2. Construct and test an anemometer.

    I will not use a datum during the process of calibrating the sensor, as this is not necessary. I will only need to compare the experimental results to analyse the accuracy of the system. Care will have to be taken throughout the calibration process and the recording of results.

  1. Planning Experimental Procedures

    I cannot measure how much the components are in contact with each other because I have no device to do so. Scientific Knowledge I am going to investigate which materials of wire have the highest resistance and I will

  2. An experiment to find how the resistance of a pencil lead varies which the ...

    the nearest millimetre), the range and number of results (30+ with repeats) and the amount of equipment needed. This is particularly useful, as I would only require two crocodile clips in addition to the other apparatus. My variable for this investigation will be how the length of the pencil lead affects its resistance.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work