Question

A current passes through a resistor. Let K1 and K2 represent the average kinetic energy of the conduction electrons and the metal ions, respectively.
(a) K2 < K2 (b) K1 = K2 (c) K1 > K2 (d) Any of these three may occur

Answer 1

(c) K1 > K2

Explanation:

Given: A current passes through a resistor. Let K1 and K2 represent the average kinetic energy of the conduction electrons and the metal ions.

Solution:

Conservation of momentum is a fundamental law of physics which stated that for a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision. If no external force is acting on the system, then momentum does not change.

Applying the above law of physics, we infer that electrons possess drift velocity which is greater than velocity of ions. Hence K1​ > K2​.

Option C is the answer.