Question

An electric dipole is held in a uniform electric field (i) Using diagram show that it does not undergo any translatory motion, (ii) derive an expression for torque acting on it.

Answer 1

No translatory motion will occur in the dipole as all the clock wise motions and anti clock wise motions will cancel out each other, so there will be no rotatory motion.

The direction of torque will be perpendicular to the direction of dipole.

The expression of torque will be $T=p\ast Esin\theta$