Question

how much work is required in turning the electric dipole from the position of most stable equilibrium to the position of most unstable equilibrium? ​

Answer 1

The condition of stable equilibrium is achieved when the direction of extrernal electric field is parallel to the direction of the dipole moment.

Hence, Potential Energy = -PEcos?

Since ?=0, cos ?=1

Thereferoe, potential energy=PE=maximum

In unstable equilibirum, the direction of the electric field is antiparallel to the direction of dipole moment.

therefore, ?=180 degrees. cos?= -1

hence, Potential enegy = -PE

Hence, total work done = Initial energy - final energy = PE - (-PE) = 2PE