• 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

# How does the length of a wire affect its resistance

Extracts from this document...

Introduction

Muna Ali-11K7

GCSE Coursework-Physics Ms Wainaina

How does the length of a wire affect its resistance?

Aim:

The aim of this investigation is to find out how the length of a wire affects its resistance in a circuit.

Introduction:

Resistance is the measure of how hard it is to get a current through a component in a circuit at a particular potential difference. Varying the resistance in the circuit can control the current through a circuit.

The greater the resistance the harder it is for the current to flow and the move energy that is converted to heat and light. Resistance is measured in Ohms (Ω).

Electricity is conducted through a wire, which also means in a wire, by free electrons. The amount and number of these free electrons depend entirely on the more material, meaning that the more free electrons there are, the better the conductor. Electrons that are free are given energy as a result of moving and colliding with other nearby free electrons. This also happens across a length of wire, which means therefore, that electricity is conducted. Resistance is the results of energy loss and heat. This involves the collisions between the free electrons and also the fixed particles of the metal, free electrons and other impurities from the metal. These electrons continually collide, and therefore these collisions result in converting some of this energy that the free electrons are carrying into heat. Therefore, the wire becomes hot.

In 1826, Georg Ohm discovered that:

Middle

I then moved the crocodile clips to 20 cm so this length of wire could be measured.I recorded the current and the voltage for 20cm of wire from the voltmeter and ammeter.I then moved the crocodile clips to 10 cm so this length of wire could be measured.I recorded the current and the voltage for 10cm of wire from the voltmeter and ammeter.This was carried out three times for each length of wire so as the result could be much more accurate and an average could be calculated for the resistance.

## Obtaining Results

Below are the results of how wire affects the resistance. Three different sets of results were collected, than an average result was calculated for the resistance. The resistance in each table was multiplied by 100 so as the results will be easier to calculate a trend in a line graph.

## Test 1

 Length Current Voltage Resistance Resistance x 100 100cm 1.03 0.10 0.097 to 3sf 9.7 90cm 0.93 0.08 0.086 to 3sf 8.6 80cm 0.94 0.07 0.077 to 3sf 7.4 70cm 0.95 0.07 0.073 to 3sf 7.3 60cm 0.96 0.05 0.052 to 3sf 5.2 50cm 0.96 0.04 0.041 to 3sf 4.1 40cm 0.97 0.03 0.030 to 3sf 3.1 30cm 0.98 0.03 0.030 to 3sf 3.1 20cm 0.99 0.02 0.020 to 3sf 2.0 10cm 1.02 0.01 0.009 to 3sf 0.9

Test 2

Length

## Current

Voltage

Resistance

Resistance x 100

100cm

0.91

0.10

0.109 to 3sf

10.9

90cm

0.93

0.09

0.096 to 3sf

9.6

80cm

0.94

0.09

0.095 to 3sf

9.5

70cm

0.95

0.07

0.073 to 3sf

7.3

60cm

0.97

0.06

0.061 to 3sf

6.1

50cm

0.98

0.06

0.061 to 3sf

6.1

40cm

0.98

0.05

0.051 to 3sf

5.1

30cm

0.99

0.04

0.040 to 3sf

4.0

20cm

1.01

0.03

0.031 to 3sf

3.1

10cm

1.02

0.02

0.021 to 3sf

2.1

Conclusion

To make and investigate the resistance further, I should have used different wires and tested them fully. Whereas in the preliminary I took only one reading of three different wires, as do that I could familiarise myself with the investigation.

I could have also changed such aspects as mentioned in the fair test section, such as changing the temperature to find out also if temperature in any way affects the resistance. I could have also changed and varied the width of the wire, as I have already found out that length of wire does affect resistance and whether the width also affects it. I could have also tested out different wire such as nickel chrome, Constantine as in the preliminary results to find out different resistances of different wires.

I could have also, to make the investigation more accurate by measuring the temperature of the wire to find out whether different lengths of wires have different temperatures so as this may affect the resistance

Overall, I feel the investigation was a success, and I believe I have achieved my aim of finding out how the length of wire affects the resistance. This is, as the length of wires increases, so does the resistance also increases, due to more electrons colliding with each other.

## Bibliography

• OCR Science Double Award B Phase 2 Modules
• Nelson Thornes “Physics For You”
• www.gcsebitesize.com
• www.howstuffworks.co.uk

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

# Related GCSE Electricity and Magnetism essays

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

3 star(s)

If it was likely to use new/tested equipments and to be able to use the same equipment for each experiment then there may be less existing argument. Accuracy on length: The only obtainable way for measuring was by ruler and hand.

2. ## How does the length of a wire affect its resistance?

The unit of resistance is the ohm. In the metre-kilogram-second (mks) system, the ratio of area in square metres to length in metres simplifies to just metres. Therefore, in the metre-kilogram-second system, the unit of resistivity is ohm-metre. If lengths are measured in centimetres, resistivity may be shown in units

1. ## Resistance and Wires

The width of the nickel-chrome wire will make a difference in the resistance of the wire because in a thin wire, there are a lot of electrons which have to travel in a proportionally small channel. This causes a lot of collision with other electrons.

2. ## Factors which affect the resistance of a wire

These impurities slow down the movement of electrons passing through the wire. This principal also applies to the thickness of wire as well. So the resistance of a wire increases as its length/thickness increases. The temperature of the wire also affects the resistance of the wire.

1. ## Investigation: How length affects the resistance in a wire.

2.44 2.43 2.44 Resistance (W) 1.64 1.66 1.64 1.64 0.7- Voltage (V) 3.99 3.99 4.00 Current (A) 2.15 2.15 2.14 Resistance (W) 1.86 1.86 1.86 1.86 0.8- Voltage (V) 4.01 3.99 4.01 Current (A) 1.85 1.84 1.85 Resistance (W) 2.16 2.16 2.15 2.16 ue theoreO ¦¨¾tà ________________ :<nð ò þ :<V*†®Ææ Z\^`pr¨ª¬¾@ B b ‚!„!¦!ª#¬#Ä#¾(À(Ô(,-º0¼0à08"8H8J8l8

2. ## How does length and width affect resistance

The electrons carrying the charge are trying to move through the wire, but the wire is full of atoms that keep colliding in the way and making the electrons use more energy. Also, Resistance is the result of energy loss as heat.

1. ## Does the length of a wire affect its resistance?

The charge is carried by 'conduction' electrons, which are not fixed, to a particular ion - they are called free electrons. When a 'potential difference' (Pd) is applied across the ends of a wire (by a battery etc.) these electrons will move towards the positive terminal.

2. ## To see how the length of a wire affects its resistance. To find the ...

* To measure the independent variable accurately we're going use specific apparatus: a metre rule with the different wires attached either end (to measure the voltage and current we're using a standard ammeter and voltmeter).We will also be carrying out the test for each wire 3 times, which will make our results more reliable and accurate when making an average.

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