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Electricity

The Resistance of Wires - Temperature.

Does the Resistance of a Wire depend on its Temperature?

As the temperature of the material increases, the ions
of the material vibrate more and this increases the
number of collisions as electrons move through the wire.
This makes the resistance of a
wire increase as the temperature of the wire increases.

A small increase in temperature may not give
a noticeable change in resistance but the
more the temperature increases, the more obvious
it becomes that the resistance is also increasing.

This increase in resistance can be clearly seen in the
current against voltage plot for a lamp.
The thin wire inside the lamp (called the filament)
becomes white hot, which causes the lamp to shine.
The increase in resistance is shown
by the curve in the current against voltage plot.

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