Electrostatics

The work done in rotating a dipole placed parallel to the electric field through \(180^{\circ}\) is W. So, the work done in rotating it through \(60^{\circ}\) is \(\left(\cos 0^{\circ}=1, \cos 60^{\circ}=\frac{1}{2}, \cos 180^{\circ}=-1\right)\)