Question

An electric dipole of moment $\overrightarrow{p}$ is placed normal to the lines of force of electric intensity $\overrightarrow{E}$, then the work done in rotating it through an angle of ${180}^{\circ }$ is

• A. pE
• B. +2pE
• C. -2pE
• D. Zero

Answer 1

The correct option is D Zero


Work done=${\int }_{90}^{270}-pEsin\theta d\theta ={\left[pEcos\theta \right]}_{90}^{270}=0$