Question

A metal rod moves at a constant velocity in a direction perpendicular to its length. A constant uniform magnetic field exists in space in a direction perpendicular to the rod as well as its velocity. Select the correct statement(s) from the following(a) The entire rod is at the same electric potential
(b) There is an electric field in the rod(c) The electric potential is highest at the centre of the rod and decreases towards its ends(d) The electric potential is lowest at the centre of the rod and increases towards its ends

Answer 1

Correct Answer : option B

"There is an electric field in the rod "

Explanation :

When a metal rod moves at a constant velocity in a direction perpendicular to its length  then :

A motional emf e= Bvl is induced in the rod

or we can also say that a potential difference is induced between two ends of rod AB.  

P is at higher potential and Q at lower potential

As there is a potential difference between two points P and Q an electric filed is setup in the rod.