Question

37 question is a doubt

Q37. In an oscillating LC. circuit the maximum charge on the capacitor is Q. The charge on the capacitor when the energy is stored equally between the electric and magnetic fields is-

(A) Q2 (B) Q/$\sqrt{3}$ (C) Q$\sqrt{2}$ (D) Q

Answer 1

Dear Student ,

The electric energy stored when energy in equally distributed, $U{\text{'}}_E=\frac{1}{2}\frac{q^2}{C}$
The energy stored in the capacitor when it is maximally charged, $U_E=\frac{1}{2}\frac{Q^2}{C}$
Now
$$\begin{gathered} U_E=2U{\text{'}}_E \\ \Rightarrow q=\frac{Q}{\sqrt{2}} \end{gathered}$$
so 2 is the right answer.
Regards