• 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

Investigate the factors that affect for the resistance of a wire.

Extracts from this document...

Introduction

Nirali Patel        Physics coursework        John Larwood

As part of my physics coursework, I will investigate the factors that affect for the resistance of a wire. E.g. length and diameter.

PLANNING

Hypothesis:

I am investigating the factors that affect a wire. I predict that the following have an affect on the resistance of the wire:

  1. The material of the wire (what is the wire made out of)
  2. The length of a wire.
  3. The cross sectional area of a wire
  4. the thickness of a wire

Resistance

The current flowing through a metal wire is proportional to the potential distance across it (providing that the temperature remains constant.)’ (physics for you by Keith Johnson) we say that a wire has a certain resistance to the current. The greater the resistance, the greater the voltage is required to push a current through a wire. Resistance is any sort of constriction in the flow.

Resistance is better described through ohm’s law:

Resistance= potential difference across the wire

                       Current through the wire

R=V

     I

Where R=resistance    

         V=volts

         I=current.

Ohm’s law

Ohms Law is states that); "Provided the temperature remains constant, the ratio of potential difference (p.d.) across the ends of a conductor (R) to the current (I) flowing in that conductor will also be constant".

(From CPG Physics complete practice and revision)

In other words, the current passing through a wire at constant temperature is proportional to the potential difference between its ends.

Resistors

...read more.

Middle

0.041

40

0.36

5.68

0.046

50

0.30

5.54

0.054

Copper wire 36 SWG (thin)

Length (cm)

Voltmeter (V)

Volts

Ammeter (A)

Amps

R=V/I (Resistance)

Ohms

10

0.50

4.02

0.12

20

0.72

3.20

0.23

30

0.82

2.94

0.29

40

1.06

2.75

0.39

50

0.95

2.4

0.4

Nichrome wire 32 SWG (thick)

Length (cm)

Voltmeter (V)

Volts

Ammeter (A)

Amps

R=V/I (Resistance)

ohms

10

1.50

0.87

1.72

20

1.63

0.45

3.62

30

1.73

0.32

5.41

40

1.79

0.25

7.16

50

1.85

0.20

9.25

Nichrome wire 36 SWG (thin)

Length (cm)

Voltmeter (V)

Volts

Ammeter (A)

Amps

R=V/I (Resistance)

ohms

10

1.56

0.45

3.47

20

1.60

0.22

7.27

30

1.70

0.15

11.3

40

1.74

0.12

14.5

50

1.79

0.10

17.9

Analysis

From the results that I got I will plot various graphs that will help me come to an end to this investigation and see whether my hypothesis was correct or incorrect.

 Graph 1

Graph 1 is a graph of the resistance of the copper SWG 24 wire against the length of the wire. From this graph, I can see that the resistance increases as the length increases. This means that the longer the wire gets, the more it will resist.

I did not get any anomalous results for this experiment as all the results I got fitted the line of best fit.

Graph 2

The second graph is a graph of the resistance of a copper wire of SWG 36 against the length of the wire. As I found out in graph one that as the length increases so does resistance, I got the same result in this graph but unfortunately, I got an anomalous result, the reading for the 50cm wire does not fit into the line of best fit. There are many reasons why this has happened and some of the reasons are:

  1. the wire was not in full contact with the crocodile clips
...read more.

Conclusion

  1. the crocodile clips were not clipped properly
  2. The wire may have coiled up and jumped to make it unfair.
  3. The wire may have been rusted or corroded which helped prevent the flow of electrons consistently, which affected the result of the experiment.
  4. The correct size of wire may not have been used.

Improvement methods

If I would be able to conduct this experiment a second time I would do the following things:

  1. conduct a preliminary experiment first so that there is a rough idea of what the actual results should be like
  2. I would repeat each wire of each thickness of each length at least 3 times and then take an average. The main reason for this is so that it is quite certain that the results obtained are correct. The experiment which I conducted above did not have more that one per wire per thickness per length.
  3. I would make sure that none of the wires are corroded or rusted or bent, I will use brand new wires so that the best possible results are obtained.

Although it was not possible in this experiment for me to take more than one reading and then take out an average for it to put for my final result I should have checked my results thoroughly and repeated any experiments were the results did not seem normal.

...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. Marked by a teacher

    Resistance Aim: my main aim is to investigate the factors that affect the resistance ...

    3 star(s)

    Charges The charge is the amount of electricity traveling through a circuit. The symbol for charge is Q The unit for charge is Coulombs A capacitor is a device that stores charge Charge (Q) = Current (I) x Time (t) Current This is the flow of electrons round the circuit.

  2. An in Investigation into the Resistance of a Wire.

    If there were any anomalous results. I would have redone that part of the experiment again to check that the results were right. But I did not have any anomalous results so I did not need to do that. So because I did not have any anomalous results that meant

  1. Discover the factors affecting resistance in a conductor.

    I did, however, feel that the multimeter experiment showed a more consistent line of best fit, so that the results were more reliable. I also felt that the Voltmeter was not an entirely accurate item of apparatus, as the results displayed were not constant and wavered quite considerably, as the

  2. To investigate the affect of wire width on electric current and resistance.

    We know that the line passes through the origin, a gradient 0/0= 0. This is the intercept, or `c' from the equation y= mx+c. y= mx+c can also be seen to be represented as r= ml; (where r is resistance, m is the resistant material and l is t/a (where

  1. Resistance of a Wire Investigation

    The resistance of a wire depends on the number of collisions the electrons have with the atoms of the material, so if there is a larger number of atoms there will be a larger number of collisions that will increase the resistance of the wire.

  2. Resistance and Wires

    They are adjusted by rotating the ratchet. This moves the spindle and thimble down the sleeve. The sleeve has numbers on it which displays the wires diameter when tightened. The table of results from the measurement of the wires is shown below: Diameter (mm)

  1. An experiment to find the resistivity of nichrome

    not be completely straight, it may be of different thicknesses throughout the length. These would have contributed as well to the error. These results would be difficult to improve on as they are reasonably accurate, and there were no anomalous results.

  2. Factors which affect the resistance of a wire

    To investigate how the thickness of a material affects the resistance of a wire I will need to calculate the resistance of wires with different gauges and compare the pattern in the resistance. I will then draw graphs for both of my experiments Method 1.

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