Copper and silicon is cooled from $300\; K$ to $60\; K$, the specific resistance
A
decrease in copper but increase in silicon
B
increase in copper but decrease in silicon
C
increase in both
D
decrease in both.
AIPMT 2001, Easy
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A
decrease in copper but increase in silicon
a The specific resistance or resistivity, $\rho=\rho_0(1+\alpha T)$
where $\alpha=$ temperature coefficient of resistivity is positive for metals (copper) and is negative for semiconductor (silicon). Thus, when cooling, resistivity decreases in copper and increases in silicon.
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