I predict that by keeping the voltage the same, the amp measurements will have a strong relationship, but by using only one voltage might be the subject of ohm’s law not to work. It may also be proven that by raising the length of the piece of wire the relationship between the resistance will be that, the longer the wire the less resistance happening. Equipments used Amp meter Volt meter (set at 4 volts) Power pack (also set at 4 volts) Experiment After setting up the equipment, I set out the circuit provided on the board. I then drew a result table to record my results and began my experiment.
I set the voltage on the power pack to 4 and clipped a crocodile clip on one end of the wire, reading 0 cm on the ruler. Then I put the other crocodile clip on the piece of wire that read 10 cm on the ruler. To get my result though I still had to move my resistor to get the se3t voltage on my volt meter (which is 4 volts). Once I achieve this voltage, I looked at the amp meter to see what amp measurement I had achieved. After writing my reading down in my table, I move the moved the crocodile clip at the reading of 10cm on the ruler and moved it to 20 cm then repeated the whole process I had just done to get the reading for 20cm.
Then I did the same process for 30cm to 90cm. once I had done this I looked at my results table to see if I could form a relationship between my results, but after looking them I couldn’t really think of a positive relationship with out any other results to compare with, but with saying that I could see a small relationship there, that the resistance goes down when the length of wire goes up. Length of wire (cm) Number of experiment 1 2 3 Resistance.
So to make sure that I had a relationship I redid the experiment again (twice) to see if my theory was try on all three tests. Length of wire (cm) Number of experiment 1 2 3 Resistance By looking at my results I came to the conclusion that my little theory was ‘the longer the piece of wire the smaller the resistance’ true but that wasn’t the end of my test. I had to find out how many ohms were in each measurement.
But first I took my table and found the average measurement for the resistance. Length of wire (cm) Number of experiment 1 2 3 Resistance Average Then I moved to do Ohms law, in order to do this I had to take the equation V=IxR and turn I round to get the number of ohms, so the end equation was R=V/I so I did this to all of my results in my table, to get Length of wire (cm).
Number of experiment 1 2 3 Resistance Average then put these results in to a graph to get one looking like figure 1. 2. Conclusion By looking at my graph I would say that my prediction is correct because the length of a piece of wire does affect the resistance of the voltage going throw it. Evaluation.
I would say that I could improve investigation by adding more detail on what I did and how I did it. I could also research more information on how to conduct my investigation further. I should have spent more time collecting information and results, which would have made my test fairer than it was all though I did do my test 3 times because I still don’t think that my test was fair enough. Kassandra McDonald 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.