A piece of copper and another of germanium are cooled from room temperature to 77° K. The resistance of

Question

A piece of copper and another of germanium are cooled from room temperature to 77° K. The resistance of (A) copper increases and germnanium decreases (B) both decreases (C) both increases (D) copper decreases and germanium increases

Tardigrade Admin · Accepted Answer

Copper is a metal and germanium is a semiconductor.
On cooling resistance of copper decreases as atomic vibrations decreases and causes a reduction in electronic collisions.
Whereas on cooling germanium, number of electrons and holes decreases and hence its resistance increases.

Q. A piece of copper and another of germanium are cooled from room temperature to 77∘K. The resistance of

copper increases and germnanium decreases

both decreases

both increases

copper decreases and germanium increases

Copper is a metal and germanium is a semiconductor. On cooling resistance of copper decreases as atomic vibrations decreases and causes a reduction in electronic collisions. Whereas on cooling germanium, number of electrons and holes decreases and hence its resistance increases.

Q. A piece of copper and another of germanium are cooled from room temperature to $7 7^{\circ} K$ . The resistance of

Copper is a metal and germanium is a semiconductor.
On cooling resistance of copper decreases as atomic vibrations decreases and causes a reduction in electronic collisions.
Whereas on cooling germanium, number of electrons and holes decreases and hence its resistance increases.