Physics - SHM Question with Solution | TestHub

Two charges, each equal to$\text{q}$, are kept at$\text{x}=-\text{a}$and$\text{x} = \text{a}$on the x-axis. A particle of mass$\text{m}$and charge${\text{q}}_0=-\frac{\text{q}}{2}$is placed at the origin. If charge${\text{q}}_0$is given a small displacement$\text{(y << a)}$along the y-axis, the net force acting on the particle is proportional to :