Drift velocity in a metallic conductor:
At room temperature there are large number of free electrons having zero average velocity, but when electric field is applied, the free electrons start moving in a direction opposite to the direction of the applied field with a velocity called drift velocity.

The magnitude of electric field set up across the ends of the conductor is given by

Options

A. `v/l`
B. `vl`
C. `l/v`
D. zero.