Question

In which orientation,a dipole placed in a uniform electric field is in (i) stable equilibrium (ii) unstable equilibrium?

Answer 1

(1)When the dipole is aligned parallel to the electric field (i.e. the angle between dipole moment and the electric field is $0^o$), then the dipole is in stable equilibrium.

(2)When the dipole is aligned anti-parallel to the electric field (i.e. the angle between dipole moment and the electric field is ${180}^o$), then the dipole is in unstable equilibrium.