Once I have my apparatus set up in the basic diagram I will adjust he settings. The wire will start off at 10cm long, once I have measured the current and voltage I will increase the length of the wire by 10cm. I will do this until the length of the wire reaches 90cm. Once I have done that I will repeat the experiment with the wire starting at 10cm and increases it by 10cm every time until it again reaches 90cm, each time recording the voltage and current. Once this has been completed I will repeat the experiment for a final time starting the wire off at 10cm long, increasing it by 10cm every time and finishing off with the wire 90cm long, once again recording the voltage and current. I will then look at my table and using the equation;
I will calculate the resistance by switching the equation around and dividing the voltage by the current therefore equalling the resistance.
I predict that as the length of wire increases that the resistance will also increase. I predict this because the longer the piece of the wire the more atoms there are for electrons to collide with than in a short wire.
Now I have completed my experiment I have shown the results in a table below.
In my method I said I would complete the investigation three times. This was to make my results more accurate; allowing me to see any results that slightly didn’t fit within the table. In my table there are a few results that slightly didn’t fit, however my results are still reliable. The results that slightly didn’t fit are highlighted below.
Even though the results that are highlighted only have a difference of 0.03 its still a huge difference for making a accurate investigation, and a huge difference for accurately measuring the resistance.
Now I have my results I can find the average resistance for each different length of wire. I recorded the average resistance in the table below.
To improve my results I could have used a more accurate ammeter because for the first piece of wire, 10cm, I was unable to read the result as the ammeter didn’t measure high enough. Now I have obtained my results I can look at them more closely.
