• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

The Electrical Resistance of Wires

Extracts from this document...

Introduction

Karim Al-shammaa

The Electrical Resistance of Wires

Plan

Introduction

In this investigation I will be looking at the resistance of wires to an electrical current and determining the factors that affect the resistance of a wire.
There are five main factors that affect the resistance of a piece of wire. These are as follows:

1) The material that the wire is made of.
2) The length of the wire
3) The thickness (or diameter) of the wire.
4) The temperature of the wire.
5) Voltage of the circuit.

However, in my investigation I will only be looking at two different factors that affect the resistance of the wire. These two factors are length of the wire and thickness of the wire.

Apparatus

For this investigation I will need several pieces of apparatus, these are as follows:

1) A ruler (to measure the length of the piece of wire that is being used).
2) Wires (to connect the circuit together)
3) A multimeter (to measure the resistance of the wire)
4) A role of Constantine wire.


Method

In this investigation I will do as follows:
As I will be investigating one variable at a time, I will need to keep the other variables constant. When measuring the length I will always use the same material: Constantan wire. Also I will make sure that the wire does not get hot by not measuring any less than 10cm. Also, I will always use the same thickness wire, 32SWG (standard gauge).

...read more.

Middle




Results

Testing the thickness

Using a 50 cm long piece of Constantan wire:

SWG

Equivalent in mm

1st attempt

2nd attempt

3rd attempt

Average

20

24

26

28

30

32

34

38

0.9

0.56

0.45

0.37

0.31

0.28

0.25

0.125

1.4

1.5

1.9

2.7

3.7

4.5

6.5

14.2

1.5

1.5

2.0

2.7

3.6

4.3

6.5

14.4

1.4
1.4
1.9
2.9
3.7
4.5

6.7

14.2

1.4

1.5

1.9

2.8

3.7

4.4

6.5

14.3

Testing the Length

Using 32 SWG (0.28mm) thickness Constantan wire:

...read more.

Conclusion


I could have made more accurate results and a more varied set of results by doing the experiment at more than just 32SWG. This would have given more varied results at different thicknesses. I could have made my results more accurate by doing the experiment more than 3 times (perhaps 5 times) and taken the average of each set of results. This would have given me more accurate results.
Inaccuracy in the results (like in the first attempt on length at 40cm) may have been due to the fact that the equipment used may not have been working properly or plain human fault. Also, when measuring the length of wire to be tested, it is possible that I may have slightly misread the length on the ruler by a couple of millimeters because of kinks and twists in the wire making it nearly impossible to get a perfectly straight piece of wire. This may have caused slightly inaccurate results.

Thickness

My results for testing the thickness were, on the whole, quite accurate with the exception of minor mistakes. This could have been due to an inaccurate length of wire, a temperature change or an inaccurate reading. However, the over all results produced a good smooth inversely proportional curve. If I were to conduct this experiment again I would have used more accurate equipment and tested more lengths at more SWGs than I did to give a more varied set of results.





...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. Peer reviewed

    Investigation in resistance in wires

    5 star(s)

    the wire gets overheated and snaps, this would lower the chances of the masses hitting somebody's foot and causing damage. To make the test fair I must keep the test as consistent as possible, for example: * The same apparatus must be used throughout the experiment * The same method must be used to collect ever set of results.

  2. Investigate the resistance of different wires and how at different lengths the voltage increases ...

    The following table shows the resistance and the temperature coefficient at 20oc of the four wires that I am investigating. Material Resistivity ? (ohm m) Temperature coefficient per degree C Conductivity ? x 107 /?m Copper 1.68 x10^-8 .0068 5.95 Manganin 48.2 x10^-8 .000002 0.207 Nichrome (Ni,Fe,Cr alloy)

  1. Resistance and Wires

    By recording the current (using the ammeter) and potential difference (using the voltmeter), change in resistance can be calculated. This data will be placed on a graph and analyzed. I will use various calculations to find the resistance of the wire (in Ohms), as different lengths of nickel-chrome are used.

  2. Resistance of wires

    If the wire is too narrow, it also tends to heat up, as friction builds because of so many electrons rushing though a narrow tunnel all at the same time. In this case, the resistance of a wire is inversely proportional to cross sectional width, because when the cross section is doubled, the resistance is halved.

  1. Investigate how the electrical resistance of a wire changes in relationship to it's length.

    The Variable factor The factor that I am going to vary is the length of the E26 wire. Circuit diagram Method The circuit was set up as shown above. A table was drawn out and the results were recorded. To improve the accuracy, compared to my preliminary results for my

  2. Resistance of wires.

    It will be necessary to do some preliminary work to determine at what voltage the resistance of the wire causes the temperature of the wire to increase, as I know that high voltage causes high current which causes heating and increasing the temperature of the wire causes the resistance to

  1. Resistance of Wires

    > keeping the same thickness of wire (which will be determined in the preliminary experiment) throughout the experiment > using the same type of wire throughout the experiment - I am using a type of wire called constantan. PREDICTION: I predict that as the length of the wire increases, the resistance of the wire in the circuit will also increase.

  2. Objective: to investigate how the rate of resistance is affected by the different thicknesses ...

    The consequence is the current will decrease and the resistance will increase. 2. Width of Wire If a wire has a long width that will mean atoms will have more space to move freely without any trouble. So this will mean that atoms wont be close to each other, like

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