Work done in rotating an electric dipole of dipole moment p (in presence of external uniform electric field ‘E’) from stable equilibrium to unstable equilibrium is

Question. Work done in rotating an electric dipole of dipole moment p (in presence of external uniform electric field ‘E’) from stable equilibrium to unstable equilibrium is

a) -2pE

b) 2pE

c) pE/2

d) pE

Answer: b) 2pE