How the length of nichrome wire affects the resistance

Authors Avatar

Aim:

To show how increasing/decreasing the length of nichrome wire affects the resistance.

Scientific knowledge:

Resistance is a force which opposes the flow of an electric current around a circuit so that energy is required to push the charged particles around the circuit. The circuit itself can resist the flow of particles if the wires are either very thin or very long.
E.g. The filament across a light bulb.

Resistance is measured in ohms. The symbol for an ohm is . A resistor has the resistance of one ohm if a voltage of one volt is required to push a current of one amp through it.

The ohm’s law shows the relations between current (I) and voltage (V) in a conductor.

As potential difference increases/decreases in the conductor, so does the current. This means that the potential difference is proportional to the current.

This is the equation used to calculate voltage, current and resistance:

 

 

         V

        I   X   R        

To work out the voltage: current x resistance

To work out the current: voltage / resistance

To work out the resistance: voltage / current

Ohm’s law is shown as: V = IR

The length of a wire:

The length of the wire will make a difference. This is because when you have a long wire, the electrons have to squeeze together for longer to be able to pass through the wire than they do in order to be able to pass through a short wire.

Join now!

The shorter the wire, the less the resistance. This is because the electrons have a shorter distance to travel, so they will not use as much energy.

Prediction:

I predict that the longest wire will have the greatest resistance. As the length of wire increases, so does the resistance. I think this because, the more the electrons flow, the more they heat up and move quicker causing them to collide with other electrons, increasing the resistance.

Plan:

Variables:

In my experiment, I am going to vary ...

This is a preview of the whole essay