- Ammeter
- Volt meter
- Voltage of the power pack
- Thickness of wire
- Same type of wire
What I think is going to happen (prediction)?
I think that the larger the distance between the two crocodile clips, the larger the resistance will be.
Reasons for giving my prediction?
My prediction says that the resistance will be higher. This is because the amount of resistance depends on the length of the wire. If the wire is short, it is more easier for the electrons from the electricity source to travel through the wire which is full of atoms, because the distance is short and doesn’t take a lot of energy, but, if the wire was long, the electrons will have to travel more further and they have to use up more energy and gradually will get slower. To make things easier lets compare it to a human being, if we were to run 20 m we would finish it easily without feeling tired, and we would still have lots of energy, but, if we were to run 2000m we would get very tired and we will use a lot of energy and when we finish we would be very tired and have no energy at all. This is exactly what the electrons do to get to the other end of the wire.
How we are going to collect results?
When we switch on the power pack we will start straight away, and we are going to be going up in measurements of five centimetres. Every five centimetres we are going to take measurements from the volt metre and amp metre. All the way up to 1m (100cm). Then after we are finished we are going to divide the voltage (volts) result by the currents (amps) results to give us the resistance (ohms). We will do this twice to give us a better vision of results and see any differences between the results. We will put the results in a table like this:
Analysis
As I explained in my prediction, the investigation came out correctly. The shorter the length of wire, the lower the resistance was going to be and the longer the wire was, the higher the resistance would be. This is because when the wire is shorter, is more easier for the electrons to travel through the wire because there isn’t a lot of atoms to push through and that means it doesn’t use a lot of energy and it will get to the end quicker. When the wire is longer, it is much more difficult for the electrons to get though to the other end because there is lots of atoms in the way and has to push its way to the other end, this will use a lot of energy and it will get to the end in a much longer amount of time.
Evaluation
The experiment went fairly well and there weren’t any major problems. But, to improve the investigation, we could have used digital volt meters and ammeters to give us an exact readings, because the normal meters didn’t give us an exact reading because the hand kept moving around a few millimetres and so we had to give an kind of estimated guess, also the hand kept on landing between two lines so we couldn’t give an exact answer and we had to round it to the nearest number. We could have used a thicker wire, because the wire we used, if you put the voltage to high, it would burn the wire and it will eventually cut into two halves. Apart from this I can say that the experiment went well and I enjoyed it.
