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

The aim of this investigation is to find out how the resistance of a wire changes when a variable is changed.

Extracts from this document...

Introduction

Resistance of a wire investigation By Seb Jenner 4/1/03 The aim of this investigation is to find out how the resistance of a wire changes when a variable is changed. The variable that I have chosen is the length of the wire. My preliminary experiment showed me that the best wire to use out of the three provided, was Constantan, this was because we found that it was a poor conductor, unlike copper, and therefore it's resistance is large and easy to read. We can not do cross section of a wire because we don't have enough range so it would have been inaccurate. Ohm's law states that provided the temperature of a conductor remains constant the potential difference across it is directly proportional to the current through it. We can calculate the resistance of something with this equation: R = V ? I (Resistance = potential difference/voltage ? current) The variables that I could have chosen were: Wire length: If the length of the wire is increased then the resistance will increase. This is due to the electrons having a longer distance to travel, which means that more collisions will occur. ...read more.

Middle

And creating more collisions between them. I predict that when I increase the length of wire the resistance will increase, this is because the electrons have a greater distance to travel therefore it will take them longer to reach the other end of the wire. More collisions between the electrons will also occur because of the more time they will spend travelling, this will also slow them down. I also believe that the resistance will be directly proportional to the length of the wire. The apparatus that I shall need is: 2 crocodile clips - to clip the connecting wires to the constantan wire 100cm constantan wire 1m ruler - to measure the length of the wire Multimeter - to measure the ohm's 2 connecting wires - to connect the crocodile clips to the multimeter. Method * First I shall collect all my apparatus (listed above) * Then I shall plug the connecting wires into the crocodile clips and the multimeter. * The first crocodile clip shall be placed at 0cm. * The second shall be placed at 10cm. ...read more.

Conclusion

1.9 30 2.6 40 3.7 50 4.2 60 5.2 70 5.9 80 6.5 90 7.4 100 8.4 I had no anomalous results and my results did not change at all which is a good sign that my readings were accurate. My results show that my prediction was correct. And that the resistance of the wire is proportional to the length. I have shown that when the length of a wire is increased the resistance increases. I believe that this is because the electrons have a greater distance to travel therefore it will take them longer to reach the other end of the wire. And more collisions must have occurred between the electrons, this would also have increased the resistance. I believe that overall my results were quite accurate, this can be seen by the line of my graph, as it goes very straight and does not waver. The inaccuracies may be due to my measuring as you can not rely on just your eyes and a metre rule to measure accurately, but it was the best that I could achieve. The metre rule is only accurate to 1mm and the multimeter is only accurate to 0.01 ohm's. ...read more.

The above preview is unformatted text

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

    An Investigation To See How Resistance Can Be Changed By Variables.

    4 star(s)

    I will be using a meter stick and carefully stuck the wire to it. This insured that the same wire is used and measured in the same way if I have to collect data on anther day. * Step one- ensure power supply is not on when putting socket into switch.

  2. Resistance of a Wire Investigation

    However, due to practical time constraints in taking the readings for my investigation, and some consequential problems relating to time extension, I could not in fact make these adjustments. The other obvious way of increasing the reliability of my results would be to take many repeat readings and find an average.

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