Investigating how the resistance of a wire depends upon its length
... Then I will adjust the current to 1 Amp all the way through the investigation. The largest length for the wire will be 100cm and the shortest I will make is 10cm. I will measure the wire with a meter ruler and stick the wire to the ruler to get an accurate measurement. I will go up in 10cm each time (10cm, 20cm, 30cm, 40cm, 50cm¡K..). I will do the experiment once then turn round the wire and do it again and do it like that until I get four readings two starting from each side of the wire. I am measuring the resistance of the wire. To make the investigation fair I will do the experiment four times, two starting from one side of the wire and two starting from the other side of the wire. This will make it fair because one side of the wire might be thicker than the other side. Then I will average all the readings off to get an accurate reading. I will make the experiments safe by making sure the wire doesn¡¦t heat up too much to start glowing. There are different ways of this happening, these are making the current too high or making the wire too short or making the current too high and the wire too short. Other ways of making the experiments safe is by not touching the wire in the middle of an experiment because the wire still might be quite hot. The thickness of the wire will be 28 SWG and will be made of Nichrome. I have based my measurements that I will use for the investigation on my preliminary work I did. The preliminary work helped me decide on a reasonable current to choose and what kind of thickness would be the best to use for top results. Analysis: The results show that the resistance is affected by the length of wire. I can tell this because there is positive correlation on the graph. The correlation means that there must be something that connects the length of wire with the resistance. Also because it¡¦s positive it means that the voltage is increasing as the current is increasing. I have found out that my prediction was right and that the longer the wire the more resistance that goes through the wire. This is because more wire means an increase ions in the wire which means the electrons have more ions to pass making it harder for them to get through the circuit therefore giving more resistance. I can tell this from my results because the line of the graph is straight which means it¡¦s a current- voltage graph. And since the current (I) is proportional to the voltage (V) it means that if I triple the voltage (V), the current (I) triples too. Too conclude I found out that the resistance is affected by the length of wire and that Ohm¡¦s law about metallic conductors is true. Furthermore the thickness of wire also depends on which wire is best to use, the thicker the wire the more resistance, therefore the best wire to use is a thi...