Consider an electric dipole comprising two charges +q and -q each with mass m , separated by a fixed distance d and initially at rest with its dipole moment pointing along i . A uniform electric field E j is turned on at time t = 0 and it is turned off at t = t_f , when the dipole moment makes an angle _f with i . Neglecting any sources of energy loss, correct option(s) is/are:

Step-by-step solution

The net force on the dipole in a uniform electric field is zero, as the forces on the two charges are equal and opposite ( qE j and -qE j ). Therefore, the center of mass remains at rest and is not deflected. Option (A) is incorrect. The moment of inertia of the dipole about its center of mass is I = m ( d 2 )^2 + m ( d 2 )^2 = md^2 2 . The torque on the dipole is = p E . The angle between the dipole moment p and the electric field E is 90^ - . The magnitude of the torque is = pE (90^ - ) = qdE . The work done by t