An electric field exerts a torque on a dipole only if:
A)the field is parallel to the dipole moment
B)the field is not parallel to the dipole moment
C)the field is perpendicular to the dipole moment
D)the field is not perpendicular to the dipole moment
E)the field is uniform

Question

Quizplus · Accepted Answer

The torque experienced by a dipole in an electric field is given by the vector product of the electric field and the dipole moment. This torque is maximum when the electric field is perpendicular to the dipole moment and minimum when the field is parallel or antiparallel to the moment. Therefore, the electric field exerts a torque on a dipole only if it is not parallel to the dipole moment. Other factors such as the uniformity of the field do not affect the torque experienced by the dipole.

An Electric Field Exerts a Torque on a Dipole Only