= Electric Current
= Wire
= Electron
Few electrons so easy to pass through
Lots of electrons so harder to pass through
Aim: To discover if and how the length of a wire effects the resistance of an electric circuit.
Plan
I am going to do an experiment to investigate if the length of a wire effects the resistance of a circuit
Safety I will have to a make sure there that I take some safety precautions before I do this experiment like the usual do not sit down while doing the experiment wear safety spectacles and a lab coat make sure the area is clear and there is no water about as we using electricity.
Fair test: To make this a fair test I will keep all aspects the same apart from the varying length of wire, although the volts passing through the circuit in the first reading was on two volts and for the last two readings was on four volts. The thickness of the wire the length of the none varying wire which connects the voltmeter ammeter battery and varying length of wire will be the same.
Prediction: I predict as the length of the wire increases the more resistance there will be in the circuit because the electrons pushing through the circuit will have more to push through as the wire length increases.
Method: Set up the circuit shown in the diagram below.
V= Volt meter
L= Different lengths of wire
A= Amp meter
Now change the length of the wire recording the amps and volts in a result table each time in order to work out your resistance.
Results
Conclusion
So my results prove that the resistance in an electrical circuit dose increase as the length of a wire dose. In my results as you go down the table with the increasing lengths of wire the resistance goes up with it all apart from the last result. Which was an incorrect set-up of the circuit.
Evaluation
The results were not as accurate as they could have been because of the flickering ammeter and voltmeter which could have altered the average reading which is what my graph is plotted on. The length of wire may have been measure imperfectly and the sallotape that held the wire down restricted the maximum length. There could also have been kinks in the wire affecting the measurement or short circuiting the wire however on the whole my experiment showed that resistance increases as the length of a wire increases.
