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

What factors affect the resistance of a wire?The reason why the length of the wire affects the resistance of the wire is because if there is more wire for the electrons to travel down, they are impeded by more stationary atoms

Extracts from this document...

Introduction

Aim: I am going to find what factors affect the resistance of a wire.

What is resistance?

The electrical resistance of an object is a measurement of its opposition to the passage of electric current. This relates to ohm’s law;

The resistance of a resistive object determines the amount of current through the object for a given potential difference across the object, in accordance with Ohm's law:

image00.png

The basics of Ohm’s Law

In electrical circuits, Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference or voltage across the two points, and inversely proportional to the resistance between them, provided that the temperature remains constant.

The mathematical equation that describes this relationship is:

image01.png

Factors

The resistance of the wire depends on the amount of atom particles in the wire that can impede the flow of electrons – this is resistance. There are four main factors that affect the resistance of a wire; the length of the wire, the thickness of the wire, the material the wire is made of, and the temperature of the wire.

The reason why the length of the wire affects the resistance of the wire is because if there is more wire for the electrons to

...read more.

Middle

0.57

0.58

0.59

0.58

8.069

Nichrome 26swg

10cm

0.62

0.60

0.62

0.61

3.66

3.58

3.61

3.62

0.169

40cm

0.69

0.72

0.70

0.70

1.44

1.45

1.43

1.44

0.486

70cm

0.86

0.86

0.84

0.85

0.87

0.87

0.86

0.87

0.977

Tinned Copper 20swg

10cm

0.07

0.06

0.07

0.07

8.18

8.17

8.19

8.18

0.009

40cm

0.13

0.14

0.14

0.14

8.44

8.44

8.45

8.44

0.017

70cm

0.20

0.20

0.21

0.20

8.34

8.34

8.34

8.56

0.023

Here are the results from these tests

From these results I concluded that I would use constantan because I found the readings constant as well as being high enough to make good sized graphs with and this would make the results reliable and more presentable.

Main Test

Using the results from my preliminary test I have decided to use the constantan wire at intervals of 10cm ranging from 10cm to 70cm as this will make for a wide range of results on my graphs.

Method

  1. Set up the circuit as shown early in this investigation
  2. Cut the wire of constantan to 70cm and insert in circuit
  3. Set the power pack to 5V
  4. Turn circuit on and write down measurements of voltage and current readings
...read more.

Conclusion

My conclusion is representative of all my data as they all showed the same conclusion so I had to remove no results. I believe my results covered a wide enough range to give an accurate conclusion that is representative of most, if not all data. All of this data is reliable and accurate so I can say this is a firm conclusion.

Evaluating my method

I had no problems with my method, the equipment I used was chosen for accuracy so I knew my results would be representative. Throughout the experiment I controlled the other factors that can affect the investigation; I controlled temperature by using 28°C (room temperature) and carefully watching a temperature gauge throughout. Another factor I had to keep constant was voltage, therefore before each test I checked the voltage coming out of the battery box with my multimeter. To control the density of the wire I used the same wire throughout the main test. I feel my results were very accurate as I used instruments to give me results instead of judging by eye which would have been the problem with the ammeter. On my multimeter I used an appropriate scale division so the readings were adequate to the correct amount of decimal places.

Reliability of conclusion

To check my conclusion were totally correct, I cross-referenced my results with two other scientists.

Bibliography:

  • http://scienceaid.co.uk/physics/electricity/images/ohmslaw.png

...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

    Investigating how the length of wire affects its resistance

    3 star(s)

    Length of wire (cm) Current (amps) Voltage (volts) Resistance (ohms) 5.0 1.6 1.0 0.6 10.0 1.0 1.2 1.2 15.0 0.7 1.2 1.7 20.0 0.5 1.0 2.0 25.0 0.4 1.2 3.0 30.0 0.3 1.3 4.3 35.0 0.3 1.3 4.3 40.0 0.25 1.4 5.6 45.0 0.2 1.3 6.5 50.0 0.2 1.4 7.0 For my preliminary experiment, I was

  2. Marked by a teacher

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

    3 star(s)

    resistance equals voltage divided by current ( R=V/I ), and voltage equals current times resistance ( V=IR ) The important factors here are the temperature. If calculations based on ohms law are produced accurate results must remain constant. And if precautions are taken there will be no significant threat to the accuracy of the results.

  1. Investigating how thickness and length affect the resistance of a wire.

    Evaluation From my graph I can see that my results that I collected are very reliable. I know this because my graph does not show any individual anomalous results. I can see on the graph that none of the results plotted are anomalous because all the points lie along the same straight line.

  2. The resistance of wire.

    Be careful when the wire is connected, as it will get hot. Be careful when cutting the wire. Make sure the mains to the power supply is switched off when removing the wire from the circuit to be measured. wwef efw esefefs ayef efba nef kcef efuk.

  1. Does the length of the wire affect the resistance?

    Increased collisions mean an increase of resistance. The thickness of the wire is another contributor. The thicker the wire the less the resistance and the thinner the wire the greater the resistance. If we look below at the diagram: If we look at the smaller circle which is representing a

  2. Investigating how the length of a Wire affects its resistance.

    It can be concluded that thinner wire has less spaces as there are less nuclei. This greatly increases the probability of a collision (or resistance) because there are fewer spaces to go through. The more spaces a wire has (i.e.

  1. Free essay

    Aim: the aim for this experiment is to check if the length of a ...

    Apparatus used: * Ammeter * Voltmeter * Power pack * Crocodile clip * Meter ruler * thermometer * Nichrome wire * Variable resistor * Wires to connect the circuit Drawing of how the apparatus was assembled: Method: 1. Collect apparatus 2.

  2. Free essay

    How the length of constantan wire affects the ressistance in a electrical circuit

    when the particles and the reactant meet they connect causing a collison this happens more frequently if the rate of reaction increases. I am going to calculate the resistance of constantan wire in which I will Resistance is can be calculated by using R= V/I where R is resistance, V is voltage and I is current.

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