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

My aim is to find the change in resistance as a current is passed through different lengths of wire as measured by ohms law (R=V/I). I kept all the other variables constant, E.g. Diameter of wire and Voltage remained constant.

Extracts from this document...

Introduction

AIM.

My aim is to find the change in resistance as a current is passed through different lengths of wire as measured by ohms law (R=V/I). I kept all the other variables constant, E.g. Diameter of wire and Voltage remained constant.

VARIABLES.

  • Temperature – an increase in temperature results in greater movement of electrons through the wire.
  • Length of wire – the longer the wire the greater distance the electrons have to travel.
  • Type of wire – some wires have more impurities that increase the resistance of current through them.
  • Diameter of wire – a thicker wire provides a greater area for electrons to pass through.
  • Number of strands in wire – more strands will increase the electron flow.
  • Density of material – higher density means more resistance because there is less space between atoms for electrons to flow.
  • Voltage & Current – an increase in voltage and current increases the movement of electrons through the wire.

HYPOTHESIS.

I predict that as the length of the wire increases, the resistance will increase as measured by the current and voltage (Ohms law).

...read more.

Middle

5

38

29

27

31

10

25

24

18

22

15

18

14

11

14

20

8

9

8

9

25

7

7

7

7

30

5

5

5

5

35

4

4

4

4

40

4

3

3

3

45

3

3

3

3

50

3

3

3

3

Resistance was calculated, as above, by the formula: R = V(Ohms Law)

                                                                       I         

These were the results:

RESISTANCE MEASURED                              (Ohms)

Length of wire (cm)

...read more.

Conclusion

I would ensure that the quality of the wire was the same through out so that the impurities did not affect my results. This could be done by ensuring the wires for the experiment were obtained from the same manufacturing batch.  

As well as making these modifications I would also improve my investigation by testing the same wire but different diameters of that wire. I would do this to expand on my investigation.

The experiment could have also been affected by other factors; for example, the wire could have been heated up during the day by the sun or any other form of heat. This would have affected the movement of the atoms within the wire.

Fig.2 shows a few anomalies. The readings of 15cm through to 30cm (15,20,25 & 30cm) and also 45cm are all above or below the line of best fit. This could be because the ammeter readings were incorrect.

In developing my investigation further, I would test how the temperature of the wire would affect the resistance measured. I would vary both the length and temperature of the wire as this would also vary the surface areas of the wire, which could affect the 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. Investigate the resistance of different wires and how at different lengths the voltage increases ...

    Electrical Conductivity (sigma) 59610000 /ohm.m How copper conducts electricity Copper is a metal. It is made up of Copper atoms closely packed together. If we could look closely enough, we would see that there are electrons moving about between the copper atoms.

  2. relationship between voltage and current

    A thicker wire, however, has less resistance, because a thick wire offers more room for an electric current to pass through than a thin wire does. A wire whose cross-sectional area is twice that of another wire of equal length and similar material has only half the resistance of the thinner wire.

  1. To find out what happens to the efficiency of a motor as I change ...

    a hairdryer turns electrical energy from a mains supply into movement energy (the fan), heat energy (to heat the air as it passes through) and sound energy (waste energy). You cannot create it or destroy it. Energy efficiency is how much of the energy you put into an appliance or

  2. Investigation into the Resistance in different lengths of wire

    flow through a piece of wire that resists them, and so heats up and gives out heat and light energy.

  1. A Resistance Investigation - Independent Variables

    If the diameter of a wire increases then the amount of material will increase thus increasing the number of positively charged ions and electrons. There is also an increases amount of space for the electrons to flow through because there is less opposition to the current so a decrease in resistance.

  2. Resistance of a wire - a number of experiments were carried out to determine ...

    Length is continuous variable and it is very simple to gather a large range of measurements. The cross sectional area and resistivity of the constantan wire used in experiment 2 will be used in the investigation because it gave some good results in the range of apparatus.

  1. Experiment to Verify Ohm's law - Resistance Course Work.

    4. The length of wire between the crocodile clips was finally reduced to 30 cm, the voltage adjusted and the current recorded. Safety I will make my experiment safe by maintaining minimal direct contact with the wire, as it will heat up due to the current passing through it.

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

    Finally I repeated the experiment twice again because by doing this I can get reliable, useful results rather than just doing it once. DIAGRAM Of The Circuit This diagram below shows how my circuit will be set up. It shows the different components and where it will be placed in the circuit.

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