• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9

Find out how the length of a wire affects its resistance.

Extracts from this document...


Hawa Mohamed-11x2


   Aim: the aim for this course work is to find out how a length of a wire affects its resistance

Variables: the factors that can affect the resistance of a wire are…..

  • Length of the wire
  • Temperature of the wire
  • Diameter and thickness of the wire
  • Material of the wire

Out of all these factors I’m only going to test the length of a wire using constantan wire and I will compare the length of the wire and its resistance

Prediction:I predict that, the longer the length of the wire, the higher its resistance. My reason for saying this is because resistance is caused in metals by free electrons bumping into ions, and for this reason they slow down in the wire. There fore more energy is lost in these collisions as heat. If the length of the wire is doubled so will the electrons that era bumping and they are bumping to the ions as twice, and there fore there will be more resistance to movement of electrons, so resistance is proportional to the length. In other words, as the length of the wire increases, so will the resistance and the number of electrons that are passing through the wire. But the current will decrease because current is the flow of electrons


...read more.



     Safety:  while I’m doing this investigationI will consider the     safety elements…….

  • ensure that I don’t touch the wire while its hot
  • I will also choose a low voltage so that it won’t over heat.
  • Further more I will not try a length of less than 10cm, this is also helped me avoid over heating.
  • I will also make sure that the area I’m doing my experiment is clean and no bags and anything else around.
  • I will be wearing safety goggles to protect my eyes from the heat.
  • I will also turn the power pack off each I’m doing the readings, because it will over heat.

    Fair testing: to make it fair testing, I will consider the factors that affect the resistance of wire are constant. I will be using the same piece of wire through out the investigation, and the same equipment, as it will decrease the chance of errors in my result.

Key factors: the length of the wire and the area of the wire are the factors that will vary. The key factors that I will change as a result are the length of the wire. The dependent variable is the resistance. However I will keep the

...read more.


     Evaluation: over all my result is quite accurate due to the fact that nearly the entire points bar sits on the line of best fit except at 100cm which is 18.2 ohms. The reason is because at 90cm the resistance was 17.7 ohms, but at 100cm it goes up high at 18.2 ohms. I think that happened because I didn’t turn the power pack off when I was reading the result for 90cm, and it got hot, so when I changed the crocodiles to 100cm, it was already hot and the voltage and current was high. If I could improve this investigation, I would let the wire cool down completely, so the temperature wasn’t high enough for that measurement, causing the resistance to be high. But after I done some research I found out that metal alloy like constantan is not affected by temperature. Therefor in this experiment ohms law does not apply. The investigation would also be more accurate if I used digital ammeter or sensors. My method was accurate because I repeated the investigation each time I got it wrong improving it more and making sure that I don’t make the same mistake.

...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)

    Because of this, electrons have more difficulty to flow through, as there is less free space. Electrons do not flow in a straight line through a conductor. Their movement is random. Therefore, as the free space is being taken by the atoms, the electrons will move around to where there is free space (even if it means they move backwards)

  2. Investigating how the length of wire affects the resistance

    This is called resistance. Less electrons (and thus current) can pass through the wire. The electron that has hit the nucleus is holding up other electrons as well as blocking a passage, which electrons can take to get to the positive terminal. This means that fewer electrons can flow through the material.

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

    A range from 10cm to 100cm is practical yet easy to spot changes and reliable. 30 measurements will be made altogether. This is 10 actual changes of length: 10cm to 100cm in 10cm increments and 3 repeats. 10 changes in length are used because too big a difference in lengths (i.e.

  2. Resistance of a Wire Investigation

    Temperature - Enzymes are used in the photosynthesis reactions of a plant. Therefore, temperature will increase the rate of photosynthesis, until a point at which the enzymes denature. Although performing the experiment at a temperature slightly higher than room temperature, perhaps 25�C, would have a positive effect on the accuracy

  1. An in Investigation into the Resistance of a Wire.

    While moving through the wire, the electrons need to squeeze together. This is because there is not enough room/space for them to pass evenly through the wire. The more they squeeze together to get through increases the chance of the electrons colliding into each other then the higher the resistance would be.

  2. Investigate how the length of a wire affects the current and resistance of a ...

    Precisely because the current is varying, besides resistance, other forms of opposition to the current arise, called reactance. The combination of resistance and reactance is called impedance; Z. when the impedance, equivalent to the ratio of voltage to current, in an alternating current circuit is constant, a common occurrence, and Ohm's law is applicable.

  1. How length affects resistance in a wire

    Preliminary Investigations Before any scientists can start an investigation they must come up with preliminary investigations to test whether there method is going to work and that it will give you reliable results. This is the same for my investigation that before I recorded my actual results I would do a preliminary to see if everything worked well.

  2. Free essay

    Investigation: How length affects the resistance in a wire.

    This would thus lead to more energy being lost (resisted), as heat. Accuracy: Accuracy is the degree of conformity of a measured or calculated quantity to its actual value: therefore to get my results as accurate as possible, I am going to use equipment that will measure the answers to

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