Physics GCSE coursework: resistance of a wire

To measure and record the results for this factor is simple; the results would be collected and could show a connection between the length of the wire and the resistance given by the wire. Ohms law, V=I/R. This says that for a certain current (charge flowing at a certain rate), there will be a greater voltage across the wire if it has more resistance. This means that the voltage measures the amount of energy used up in getting each coulomb of charge through the wire. The units of volts are the same as joules per coulomb. Therefore, Ohms law says the more resistance means more energy used to pass through the wire. Resistance is a measure of how much energy is needed to push the current through something. The electrons carrying the charge are trying to move through the wire, but the wire is full of atoms that keep colliding in the way and making the electrons use more energy.

Equipment

• Wires
• Battery/Power pack
• Voltmeter
• Ammeter
• Crocodile Clips
• Ruler
• Resistance wire

Method

1. First of all I will get together all the apparatus I need and set it up.

2. Then making certain that one of the crocodile clips is on exactly 0mm and that the other is on exactly 400mm I would take a reading and after taking a reading I will increase the length by 50mm 5 till I get too 600mm.

3. Before I record the reading I would make sure that the ammeter is correctly connected so that the reading would be as accurate as possible.

5. Then I would repeat the whole experiment making sure that I used the same wires so that the width and material of the wire were kept constant. But this time change the voltage to 6 volts from 4 volts.

6. Whilst repeating the experiment I would make sure that I did it in the same place as before because if I repeated it next to a radiator the resistance would go up.

Results 1

Results 2

With both sets of results I have rounded the results to 2 decimal places. This is so that the results are accurate and when reading them they are easier to understand.