Same chapter3 marksDifficulty: Medium
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3 marksDifficulty: Medium
How does the resistivity of a metal and of a semiconductor change with temperature, and why?
Original Khojo Papers practice question — not from a past board paper.
Answer
The resistivity of a metal increases with temperature, because the lattice ions vibrate more and scatter the free electrons more often. The resistivity of a semiconductor decreases, because a rise in temperature promotes many more electrons across the energy gap and the increase in the number of charge carriers outweighs the increased scattering.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
This is why a semiconductor has a negative temperature coefficient of resistance.
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