Question

The angle at which maximum torque is exerted by the external uniform electric field on the electric dipole is ______.

• A. \( 0^\circ \)
• B. \( 30^\circ \)
• C. \( 45^\circ \)
• D. \( 90^\circ \)

Hint:

Torque is maximum when the dipole is perpendicular to the electric field (\( \sin 90^\circ = 1 \)).

Answer 1

The Correct Option is D

Torque on an electric dipole in a uniform electric field is \( \tau = pE \sin \theta \), where \( p \) is the dipole moment, \( E \) is the electric field strength, and \( \theta \) is the angle between the dipole and the field. Maximum torque occurs when \( \sin \theta = 1 \), i.e., \( \theta = 90^\circ \).
Answer: \( 90^\circ \).