The energy required to charge a parallel plate condenser of plate separation d and plate area of cross-section A such that the uniform electric field between the plates is E, is

Options

(a) ε₀E² Ad
(b) 1/2 ε₀E² Ad
(c) 1/2 ε₀E²/ Ad
(d) ε₀E² /Ad

Correct Answer:

1/2 ε₀E²/ Ad

Explanation:

The energy required to charge a parallel plate condenser is given by U = 1/2 CV²
As C =ε₀ A / d and V = E.d
U = 1/2ε₀ A / d . E²d²
= 1/2ε₀ E² Ad