Q.
A dipole of electric dipole moment p is placed in a uniform electric field of strength E. If $\theta$ is the angle between positive directions of p and E, then the potential energy of the electric dipole is largest when $\theta$ is
A) $\frac{\pi}{4}$
B) $\frac{\pi}{2}$
C) $\pi$
D) Zero
Explanation
(c) Dipole energy
$U = - pE\ cos\ \theta$
When U is maximum
$\cos{\theta = - 1}$
$\ \ \ \ \ \ \theta = \pi$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.