Electrostatics

The bob of a simple pendulum of length '\(L\)' has a mass '\(\mathrm{m}\)' and charge '\(\mathrm{q}\)'. The pendulum is suspended between the plates of a charged parallel plate capacitor. The direction of electric field is shown in figure. The period of oscillations of the simple pendulum is (acceleration due to gravity \(\mathrm{g}>\mathrm{qE} / \mathrm{m}\) )