wire coursework
...th of the wire, you should also double the amount of atoms causing the resistance. For example; in a 10cm wire, the electrons would have to travel double the distance they would have needed to in a 5cm wire. This means that the amount of atoms the electrons need to collide with would also double, as would the resistance. Results: LENGTH CM VOLTAGE V CURRENT I RESISTANCE = V IN §Ù I 5 0▪15 0▪4 0▪375 10 0▪35 0▪4 0▪875 15 0▪50 0▪4 1▪25 20 0▪67 0▪4 1▪675 25 0▪86 0▪4 2▪15 30 1▪03 0▪4 2▪575 35 1▪16 0▪4 2▪9 40 1▪35 0▪4 3▪375 45 1▪53 0▪4 3▪825 50 1▪8 0▪4 4▪5 Analysis: The results from the graph give a clear indication of how the resistance compares to the wire length. It shows that when the length of the wire increases, the resistance also increases. It also shows that the results are directly proportional, which means that when you double the length of the wire you also double the amount of resistance. Look at my results, a 20cm wire has a resistance of 1▪675 ohms and a 40cm wire has a resistance of 3▪375 ohms. This is almost exactly double. The theory behind this is explained in the prediction which turned out to be correct. In every single metal wire, there are a number of atoms and free moving electrons. Electricity is the movement of these electrons through the wire. Resistance is caused when the electrons moving through the wire collide with atoms which makes it harder for them to pass through the wire. This means that the more atoms there are to collide with, the harder it is going to be for the electrons to pass through, this increases the resistance. In a length of wire there is a number of atoms, and in a wire twice the length, there will be twice the amount of atoms. This m...