A dipole of an electric dipole moment p is placed in a uniform electric field of strength E. if `theta` is the angle between positive direction of p and E, then the potential energy of the electric dipole is large when `theta` is

Options

A. `pi/4`
B. `pi/2`
C. `pi`
D. zero

Answer

C

Explanation

`:.` The potential, `U=-p*E=-pEcos theta`
`:.` U is maximum, when `theta=pi`.