ELECTRICAL RESISTANCE

2 marks · Easy

Explain why the resistance of a wire increases if its temperature increases.

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As temperature increases, atoms in the wire vibrate more, making it harder for electrons to flow, so resistance increases.

Also accept: Increasing temperature causes more collisions between electrons and atoms, raising resistance

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Marking points

B1 · 1 mark · States that atoms vibrate more at higher temperatures.

B2 · 1 mark · Explains that increased vibration/collisions make it harder for electrons to flow (increase resistance).

Worked solution

At higher temperatures, the atoms in the wire vibrate more. This makes it more difficult for the electrons to pass through, so the resistance increases.