Resistance of a Wire :: Papers

Resistance of a Wire Introduction Resistance is the opposition a material offers to the flow of electricity. The electrical resistance of an object is not only by what material it's made of, but also by its shape. A very thin copper wire has more resistance than a thick copper wire of the same length. A very long copper wire has more resistance than a short one of the same thickness. Resistance is measured in Ohms. Variables There were three variables that our group was able to choose from; the length of the wire, the area of the wires cross section (thickness) or the type of wire (constantan or nichrome). All of these variables are able to change the resistance of the wire. Here are my thoughts and predictions on what would happen to the resistance of the wire as you change the variables. I think that if you change the length of the wire then the resistance would increase as the length increased but the current would decrease. If you changed the thickness of the wire then the resistance would decrease as the wire got thicker but the current would increase. If you change the type of wire then you will receive different results, as there may be more or less resistance between types of wire. To study the resistance or wire we experimented on changing the length of nichrome wire. We measured the volts and amps over 1 metre; I worked out the resistance using my calculator. We carried out this experiment 5 times to make the results fair. We let the wire cool down a bit between doing the experiments, as its temperature did tend to increase as we got to the end of each experiment. Analysis We took a set of practice results before starting the experiment. Here they are. Wire Volts Amps Ohms 10cm 2.63 2.53 1.04 50cm 4.16 0.82 5.