Question

An electric dipole has the magnitude of its charge as q and its dipole moment is p. It is placed in a uniform electric field E. If its dipole moment is along the direction of the field, the force on it and its potential energy are respectively

(a) 2q.E and minimum

(b) q .E and p.E

(c) zero and minimum

(d) q.E and maximum

Answer 1

Correct option (c) zero and minimum

Explanation:

The total force on dipole is zero because F =qE is applied on each charge but in opposite direction. The potential energy is U = vector -p  vector E which is minimum when vector p and vector E are parallel.