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

Factors affecting the resistance of a wire.

Extracts from this document...


Hannah Marchant


Factors affecting the resistance of a wire


Resistance is a force, which opposes the flow of an electric current around a circuit so that energy is required to push the charged particles around the circuit. The circuit itself can resist the flow of particles if the wires are either very thin or very long. E.g., The filament across an electric bulb is quite thin as it needs to resist the flow of particles for the bulb to glow.

Resistance is measured in ohms. George Ohm discovered that the electromotive force of a circuit is directly proportional to the current flowing through the circuit. This means that if you triple one, you triple the other. He also discovered that a circuit sometimes resists the flow of electricity. He called this resistance. He then came up with a rule for working out the resistance of a circuit :

V/I = R

V - Volts

I - Current

R - Resistance.

Plan: Three external factors influence the resistance in a conductor. Thickness (cross sectional area of the wire), length, and temperature all have some effect on the amount of resistance created in a conductor. The fourth factor is the conductivity of the material we are using. Some metals are just more electrically conductive than others are. This however, is considered an internal factor rather than an external one.

For the

...read more.


 we will observe the reading on the voltmeter change as we change the current to 0.25 A. We also observe a general increase in the voltage, as the length of wire we use gets longer. The rheostat will also be set at different positions for the different lengths of wire that we use.

Evidence: to make sure our overall values are as accurate as possible we will repeat our readings and then take the mean resistance. We will also be able to spot and discard any anomalies from our results.  


Set of results 1


(V) Volts

(   ) Amps

























...read more.


I do not think that doing any more results in our experiment would have made it any more accurate.

        During my experiment, I have noticed several modifications I could make to improve on the Investigation if I was to repeat it. I could use pointers instead of crocodile clips; I would do this because pointers would be more accurate. The pointers would be more accurate because the tips have a much smaller area than the crocodile clips giving a more accurate measurement of the length of wire. Perhaps where we to have a bar that didn't bend in place of the wire, it could have been more accurate.

As well as making these modifications, I would also improve my Investigation by testing the same wire but with different widths of that wire. I would do this to expand on my Investigation. I could also try to work out the resistivity of the wire, we could do this by using the formula (                  ) and then work out the percentage of error in our results.

This document was downloaded from Coursework.Info - The UK's Coursework Database

Click here to visit Coursework.Info/

...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

    The factors affecting the resistance of a metalic conductor.

    4 star(s)

    The steeper the slope, the higher the resistance. You can see that the 15cm wire is the steepest line, the second is the 30cm wire and the least steep line is the 45cm wire. The steeper the line, the higher the gradient.

  2. Physics GCSE Coursework:Factors affecting the resistance of a wire

    Prediction: I predict that as the cross-sectional area of the wire widens and increases the resistance will also increase because it is proportional to the cross-sectional area. If the cross-sectional area doubles or trebles, so will the resistance accordingly. Again I can use my preliminary work as a source and

  1. Resistance Coursework

    I also found out that the resistance of one amp carries a current of one amp if there is a potential difference of one volt across it. Judging from my results, I can safely say that the majority of my prediction was right.

  2. The aim of this investigation is to investigate the factors affecting the resistance of ...

    Chrome 30 125 20 2 1.5 Nickel Chrome 30 125 20 3 1.5 1.5 2.7 Nickel Chrome 30 125 30 1 1.3 Nickel Chrome 30 125 30 2 1.3 Nickel Chrome 30 125 30 3 1.3 1.3 3.1 Nickel Chrome 30 125 40 1 1.1 Nickel Chrome 30 125 40

  1. Discover the factors affecting resistance in a conductor.

    We can use this formula to make calculations with all values for V for a given conductor. However, the resistance may change is the conductor heats up. Many laws in physics are stated to be unbreakable, however this is not how Ohms Law is defined.

  2. Resistance of a Wire Investigation

    of photosynthesis, which could lead to the question of whether or not other types of light, such as fluorescent lights or halogen lights, would have a different effect on the rate of photosynthesis. TENTH PHOTOSYNTHESIS INFORMATION: The Nature of Light Light behaves both as a wave phenomenon and as discrete particles of energy called photons.

  1. Investigate one or more factors affecting the resistance of metal wires

    This material was Constantan. Constantan is a metal alloy, which shows very small resistance change with temperature under normal laboratory conditions (Constantan only increases resistance by about one-hundredth-thousandth part per Kelvin rise in temperature). Knowing this fact, I decided that I would base my main experiment on constantan rather than

  2. Factors affecting Resistance of a wire

    I predict that with a wire length of 100cm, the resistance will be lowest. I say this because in such a short wire there are not so many particles for passing electrons to collide with. You could compare it to a high street that you are walking down.

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