Question

When no current is passed through a conductor,
(a) the free electrons do not move
(b) the average speed of a free electron over a large period of time is zero
(c) the average velocity of a free electron over a large period of time is zero
(d) the average of the velocities of all the free electrons at an instant is zero

Answer 1

Answer:

b is the correct answer

Answer 2

The common velocity of a free electron over a considerable period of time is zero & at an instant is zero.

Explanation:

• When no current is passed through a conductor then there will be no net charge transfer through it. At this time the free electrons (e) are in random motion.
• Hence there is no movement of electrons then the net charge transfer through the cross-section of the conductor is zero.
• Because of no net charge transfer at any point, it leads that the average of the velocities of all the free electrons at an instant is zero.
• As each electron is moving in a random way and there is no net transfer of charge. From this, we can be concluded that the average velocity of a free electron over a large period of time is zero.