when an electric dipole is suspended in a uniform electric field, then under what conditions the dipole is in (i) stable equilibrium and (ii) unstable equaliibrium.

Explanation

The dipole in an electric field will be in stable equalibrium if the following conditions are satisfied :
(i) The resultant force on dipole is zero, i..e, there is no translatory motion of dipole. (ii) The torque on dipole is zero, i.e, there is no ratatroy motion pf dipole is minimum.
it will be so when dipole will be so when dipole is aligned along lthe direction lof electric field.
The dipole will be in unstable equalibrium if (i) the resultant force on diople is zero. (ii) the torque on the diople is zero. (iii) the potential energy of dipole is maximum.
it will be so when diple is aligned opposite to the direction of electric field.