Two identical point charges are fixed apart on a horizontal line
PHYSICS · Single correct · CBSE · Physics · Electric Charges and Fields · Electric Charges and Fields
Problem
Two identical point charges +q are fixed 20cm apart on a horizontal line. A third identical charge +q is placed exactly midway between them and then given a very small displacement perpendicular to the line joining the fixed charges. Which statement correctly describes the subsequent force experienced by the displaced charge?
(a) The net force is zero; the charge remains in neutral equilibrium.
(b) The net force is directed away from its original position; the equilibrium is unstable.
(c) The net force is directed towards its original position and proportional to the displacement, so the equilibrium is stable.
(d) The net force is directed towards its original position but inversely proportional to the square of the displacement.