The fourth and final part will be evaluating my investigation, I will say if it could have been improved and if it worked as expected.
APPARATUS
I will need a Digital ammeter and a digital voltmeter because the readings given are a lot closer than with an analog one. I will need just over a meter of 0.19mm thick nichrome, a meter stick, a power supply, some wires and two crocodile clips
PLANNING
I have been given a piece of wire called Nichrome, which has a thickness of 0.19mm.
I will connect this into the circuit using crocodile clips, I will stretch the wire across a meter stick and connect one crocodile clip at 0cm and one at 10 cm, I will record a reading from both the ammeter and the voltmeter, I will then move the crocodile clip which is on 10cm to 20 cm and again take a reading from both the ammeter and the voltmeter before recording the results into a table.
The variable for my experiment will be the length so to keep it a fair test I must use 10 cm jumps each time, use the same metal each time meaning it must be Nichrome of 0.19mm. I will eventually have a full table of results ranging from 10cm to 100cm.
PREDICTION
I predict that as the length of the wire increases, the resistance will increase. I predict this will happen because Resistance is due to the atoms in the wire. The electric charges will collide with the atoms, slowing them down. If the wire is longer, then there are more atoms in the way of the charges so the resistance will increase. The resistance will depend directly on the number of atoms in the wire. I have indicated in the rough graph below on what I think will happen and what it will then look like on the graph.
RESULTS
Second set will now be recorded before finding the eventual average
I will now go on to plot the graph before recording my conclusion.
Conclusion
After recording my results and plotting the graph I can say that my prediction was correct. This shows that resistance is greater the longer the wire is because there will be more atoms for the electrical charges to hit the atoms and get slowed down. From what my results say I am willing to predict that if I had a thicker piece of Nichrome say 0.37mm thick then the resistance would be even greater because not only will the length give more resistance but now that it is thicker will mean there will be space for more atoms.
This will
