I also predict that the thicker the wire the smaller resistance it will have. I predict that the graphs will be linear graphs because I is proportional to V. Results: Copper-26 Size (Cm) P. D. (V) Current (A) RESISTANCE (? )
Average 0. 357 What I found out: I found out through my graphs and tables that resistance increases as the length of the wire increases, this also proves that my prediction was correct that I is proportional to V. I also spotted two patterns concerning the P. D and the Current columns. As the length of wire increases the P. D. also increases, also as the wire increases the current decreases. Nichrome has a very high resistance so it would be a lousy conductor; this is because it would not let electricity flow through it easily.
Whilst Copper has a very small resistance so it would be an excellent conductor. We should have known that copper is a good conductor because the wires on house appliances are made from copper. Constantin has a relatively large resistance, at least in the same size as the copper and Nichrome that we have just been talking about. As the cross sectional part of the constantin wire decreases so does the resistance, so constantin would be my second choice to use as a wire. All electrical components resist a current flowing through them.
The bigger the resistance the lower the p.d. The bigger the resistance the bigger the voltage needed to produce a particular current. When components are connected in series their total resistance is the sum of their separate resistances. I also found out why it is unsafe to have the voltage higher than 2. This is because the wire burns creating a fire hazard. In the constantin-26, the 3rd voltage and current row is significantly less than the other two, therefore it produces a larger resistance than the other two. This boosts the average resistance up by a substantial amount.
This may have happened because the power pack was set on a lower voltage, maybe 1 volt for example. If this is right and the results are incorrect then constantin-26 would have a very low resistance like in 22 and 18. We could improve the reliability of this experiment by simply taking more results e. g. by using say 100cm-150cm of wire, this would add 6 more results to our charts, so it is nearly doubling the current accuracy. We could take larger range of sizes and more different materials. Also if I had enough time I would repeat the constantin experiment again because I think it is incorrect.
I think if we did all the experiments on the same day this would improve our results reliability because we may get different equipment which may not work correctly and the temperature will stay the same over one day but over the days we completed the experiment the temperature varied; one day it was raining and the next it was sun shining. Show preview only 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.