A piece of copper and another of germanium are cooled from room temperature to $80\, K$. The resistance of :-
A
each of the them increases
B
each of them decreases
C
copper increases and germanium decreases
D
copper decreases and germanium increases
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D
copper decreases and germanium increases
d Copper is metal and germanius is semiconductor. Resistance of a metal decreases and that of a semiconductor increases with decrease in tempertaure.
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