Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  • Level: GCSE
  • Subject: Science
  • Essay length: 1442 words

Does the length of wire in a circuit affect the resistance? Plan The aim of this investigation is to find out whether the resistance increases or decreases

Extracts from this essay...

Introduction

Does the length of wire in a circuit affect the resistance? Plan The aim of this investigation is to find out whether the resistance increases or decreases as the length of wire increases. The key factor that I plan to investigate is the length of wire, and I will alter the lengths of wire, and measure the resistance during the investigation using an ammeter and a voltmeter. The diagram above shows wire in a circuit. The current is hitting the wire particles, which slow the current down. I predict that the longer the wire, the higher the resistance and the lower the current. The reason for this prediction is that when the current goes through a wire, the current hits the particles of the wire, which slow it down over a longer period of time. The path of an electron is not just a simple direct route from negative to positive, but an electron has a zigzag path, as electrons constantly collide with particles of wire. So the more collisions there are, the more friction there is, acting as the opposite force, and therefore slowing the current down. If we have a longer wire, we are forcing the current to go through a wire-full of particles for longer; therefore the current will slow down after hitting more particles inside the wire.

Middle

Therefore I will measure the wire at different lengths at the same voltage, keep the material of the wire the same all through the experiment, and leave the wire for a couple of seconds to let it cool down. I will also use the same method to obtain every reading. Just in case, I will carry out the experiment in the same room, at the same room temperature, to be sure that the surrounding temperature did not affect my experiment. I will also repeat the experiment, and do it three times in total. I would like to collect as much readings as I can, so I will take readings every ten centimetres. This would mean that I would see a clear pattern. Observations 1. Length of wire (cm) Current (a) Voltage (v) Resistance (?) 100 1.77 2.17 1.22 90 2.13 1.93 0.90 80 2.10 2.97 1.39 70 2.30 2.03 0.88 60 2.64 1.97 0.74 50 2.76 2.04 0.73 40 3.11 1.94 0.62 30 3.05 1.85 0.60 20 4.50 1.69 0.37 10 5.69 1.45 0.32 2. Length of wire (cm) Current (a) Voltage (v) Resistance (?) 100 0.50 0.60 1.20 90 0.54 0.59 1.08 80 0.58 0.57 0.98 70 0.65 0.55 0.85 60 0.71 0.53 0.75 50 0.81 0.50 0.62 40 0.94 0.46 0.49 30 1.06 0.41 0.39 20 1.32 0.31 0.22 10 1.74 0.23 0.12 3.

Conclusion

To improve this experiment I would set up a few of circuits that are exactly the same, using the same wire that is cut into metre long fragments. Then I would use them one by one on each length to avoid the heating of wire. Another way to improve the experiment is to use laboratory equipment instead of equipment designed for school use. I would have done it this way, but we did not have the resources to do this in the unsafe environment of a classroom. The evidence I have collected is not very reliable because the scientific equipment used in schools can never be as accurate as scientific equipment used in laboratories. Additional evidence could be finding the relationship of resistance through different widths of wire, but for this experiment you would have to get different wires, and possibly create different circuits. In conclusion: I think that the investigation was realized in the best way possible, giving the time deadline and resources. I am sure that if we had more accurate and new equipment available, these results would all be on the line of best fit. My prediction was correct, as the line does go upwards revealing the link connecting resistance and length of wire: if one increases the other increases as well. ?? ?? ?? ?? Katarzyna Lakus Page 1 5/10/2007

The above preview is unformatted text

Found what you're looking for?

  • Start learning 29% faster today
  • Over 150,000 essays available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Over 180,000 student essays
  • Every subject and level covered
  • Thousands of essays marked by teachers

Related GCSE Electricity and Magnetism

  1. p5 investigation cwk- resistance of a lightbulb

    Constantan and manganin are two similar type of filament wire as they have less resistance than nichrome, which has a very high resistance. I can see this from my graph and tables as the average resistance for constantan is 1.29?

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

    Take 5 readings for each length of wire. Step 6 Then repeat steps 2-5 again but for the following lengths 95cm, 90cm, 85cm, 80cm, 75cm, 70cm, 65cm, 60cm, 55cm, 50cm, 45cm, 40cm, 35cm, 30cm, 25cm, 20cm, 15cm, 10cm (stop at 10cm because the wire would be too short and it would start to heat up and would soon break).

  1. Resistance of a Wire Investigation

    945 21 5 1015 21 Although this is a very quick, simple and efficient way of obtaining an idea of the trends for the graph, and the boundaries for the measurements, this experiment was not in itself in my opinion accurate enough to be the basis of my main experiment.

  2. How does length and width affect resistance

    Torches, some Christmas tree lights, and other simple devices use series circuits. In a parallel circuit, the current splits to flow through two or more paths. Parallel circuits enable a single energy source to provide current to more electric devices than a series circuit could.

  1. To Investigate the Relationship between the Resistance and the Length of a Wire

    Therefore as the length of the wire increases, the number of obstructions increases proportionally. An increase in the obstructions, increases the resistance. The resistance of a wire, not only depends on its length but also its thickness and shape (Physics 1).

  2. Length vs Resistance

    Thickness of wire: 0.25mm (Power pack set to 2V) Length (cm) Voltage (V) Current (A) Resistance (?) 10 0.70 0.58 1.21 20 1.15 0.50 2.30 30 1.23 0.36 3.42 40 1.29 0.28 4.61 50 1.32 0.23 5.74 60 1.33 0.19 7.00 70 1.34 0.16 8.38 80 1.33 0.14 9.50 90

  1. Factors which affect the resistance of a wire

    The second experiment was to give me a rough idea of what the pattern in resistance was when the thickness of the wire was increased And the third experiment was to help me decide which material I am going to use in my practical experiment that will give me the most accurate results.

  2. Investigate the resistance of different wires and how at different lengths the voltage increases ...

    more collisions between the atoms and electrons which will then cause- the resistance to rise To rise. I cannot control this variable as it is very difficult and as I don't have the correct the equipment to do so but I can minimize the heating affect by doing preliminary results

  • Over 180,000 essays
    written by students
  • Annotated by
    experienced teachers
  • Ideas and feedback to write
    your own great essays

Marked by a teacher

This essay has been marked by one of our great teachers. You can read the full teachers notes when you download the essay.

Peer reviewed

This essay has been reviewed by one of our specialist student essay reviewing squad. Read the full review on the essay page.

Peer reviewed

This essay has been reviewed by one of our specialist student essay reviewing squad. Read the full review under the essay preview on this page.