question_answer

An electric dipole of moment \[\vec{P}\] is placed in a uniform electric field \[\vec{E}\]. If the dipole is slightly rotated about an axis perpendicular to the plane containing  \[\vec{E}\] and \[\vec{P}\] passing through the center of the dipole, the dipole executes simple harmonic motion. Consider I to be the moment of inertia of the dipole about the axis of rotation. What is the time period of such oscillation?

A) \[\sqrt{\left( pE/I \right)}\]

B)         \[2\pi \sqrt{\left( I/pE \right)}\]

C) \[2\pi \sqrt{\left( I/2pE \right)}\]

D)        None of these