The resistance of the wire will be measured Essay Example for Free

The resistance of the wire will be measured Essay There were 3 types accuracy equipment we used:   Ruler which was accurate to + or 1mm   Ammeter which was accurate to + or 0. 01 amps Voltmeter which was accurate to + or 0. 01 volts To make sure our results were fair we did each result 3 times, worked out a resistance and then worked out the final resistance. Making it Fair We did certain things to keep the investigation fair:   We used the same lengths of wire each time. We used the same current each time.   We used the same material each time. Safety To make our investigation as safe as possible, we tried work in a safe and tidy environment which was not overcrowded. We also worked with less than 1 amp because it might overheat and there would be a danger of burning. We switched off the power when we were changing the wires to avoid getting burned. We did not cut the wire from the reel to avoid getting cut. Results We have tested constantan in this investigation. Material Length of wire (cm) Current A B C Voltage A B C Resistance A B C Average 24 swg Material Length of wire (cm) Current A B C Voltage A B C Resistance A B C Average 26 swg 7 Material Length of wire (cm) Current A B C Voltage A B C Resistance A B C Average 28 swg Material Length of wire (cm) Current A B C Voltage A B C Resistance A B C Average   Material Length of wire (cm) Current A B C Voltage A B C Resistance A B C Average   Conclusion The results in all the tables show that the resistance increases each time the length of the wire is increased, as shown in all of the tables above. The length of the wire affects the resistance of the wire because the number of atoms in the wire increases as the length of the wire increases. The resistance of a wire depends on the number of collisions the electrons have with the atoms of the material, so if there is a larger number of atoms there will be a larger number of collisions, which will increase the resistance of the wire. Evaluation After doing this experiment, I have come up with a reliable set of results. Even though I have achieved a good set of results there are obviously going to be errors, which I have made that could affect the investigation. The errors that I came across were, the wire was very hard to get straight and had bends, the voltmeter was only accurate to two decimal places so the voltage was flickering which made it hard to tell what the exact number was. To make my accuracy better we could have done more than ten lengths, done each result more than three times, used ammeter and voltmeter sensor. We could also have used different cross sectional areas or use different materials. I think my graph was good to look at but there are still one or two anomalous results which could have been caused by accuracy measuring instruments which we could have improved. To support my conclusion I could do some extra work like testing more materials to see what other materials it would work with. We could test more length to see if the graph will rise in proportion or will there be a point where the graph will bend and the resistance will not go any higher. 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.