Question

What orientation of an electric dipole in a uniform electric field corresponds to its (i) stable and (ii) unstable equilibrium? [CBSE Delhi 2010][HOTS]

January 13, 2024

Answer

(i) In stable equilibrium the dipole moment is parallel to the direction of the electric field (i.e., θ = 0).

(ii) In unstable equilibrium PE is maximum, so θ = π, i.e., the dipole moment is antiparallel to the electric field.

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