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The Resistance of Wires - Length.

Does the Resistance of a Wire depend on its Length?

The resistance of a wire changes if its length changes.
This makes sense if you consider that there are a
number of collisions between the electrons and the ions
when electricity flows through 1 metre of a wire.
There are twice as many collisions when electricity
flows through 2 metres and 3 times as many
collisions when electricity flows through 3 metres etc.

If we plot this on a graph
we get a straight line relationship as shown below.

Plot for Resistance and the Length of a Wire

As long as the material, thickness and the temperature
of a wire stays the same then the resistance
is directly proportional to the length of the wire.
Doubling the length of the wire will double the resistance.

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