Question

Write the expression for the torque \[\vec{\tau}\] acting on a dipole of dipole moment  \[\vec{p}\] placed in an electric field \[\vec{E}\].

Answer 1

The torque \[\vec{\tau}\] acting on a dipole of dipole moment \[\vec{p}\] placed in an electric field \[\vec{E}\] is given by

\[\tau^\rightharpoonup = \vec{p} \times E^\rightharpoonup \]

\[\text { or }\]

\[ \tau^\rightharpoonup = pE\sin\theta\]

\[\text { where } \]

\[\theta = \text { Angle between dipole moment and electric field }\]