To find how the resistance of a wire varies with length

Investigation – To find how the resistance of a wire varies with length

1st Section – Prediction and Planning

Introduction: I am going to conduct an experiment to investigate how the electrical resistance of a wire changes in relationship with it’s length.

Prediction and Planning: I think and have good reason to believe that as the length of the wire increases, the resistance will increase too. Not only that but I also believe that the rate at which the resistance of the wire increases will be directly proportional to it’s length. My reason for thinking this is that in atoms of all conductors they have free electrons in the outer shell of their structure. It is because of this structure that the outer electrons can move about freely, even in a solid. When there is potential difference across a conductive material all the free electrons arrange themselves in lines going in the same direction (this is electric current). Resistance occurs when charged particles in the current collide with fixed particles in the material. So as you increase the resistance of a material you also need to increase the force used to push the current.

Resistance (ohm’s/Ω) = Volts divided by Current (Amperes)

This is Ohm’s Law, However it only applies if the temperature of the wire stays constant.

This means that as the length is increased so is the number of collisions and so the resistance.

This is the circuit that I will be using:

What we did was start with 500mm of nichrome wire then go up to 600mm and 700mm ect until we got to 1200mm. We took readings every 100mm, which consisted of measuring the ...