Copper is metallic conductor and germanium is semiconductor therefore as temperature decreases resistance of good conductor decreases while for semiconductor it increases.
JEE Main 2004 — Physics Electromagnetism
A piece of copper and another of germanium are cooled from room temperature to 77 K, the resistance of
Held on 30 Apr 2004 · Verified 6 Jul 2026.
each of them increases
each of them decreases
copper decreases and germanium increases
copper increases and germanium decreases
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A square loop of side $2$ cm is placed in a time varying magnetic field with magnitude as $B = 0.4\sin(300t)$ Tesla. The normal to the plane of loop makes an angle of $60°$ with the field. The maximum induced emf produced in the loop is __________ mV.
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