In an oscillating LC circuit the maximum charge on the capacitor is Q. When the energy is stored equally between the electric and magnetic fields, the charge on the capacitor (q) is

Two coils P and S have a mutual inductance of ($\pi$) mH. The secondary coil S has resistance $4\,\Omega$ and self inductance $(60/\pi)$ mH. If the current in the primary is $I_p = 12\sin(50\pi t)$, then the maximum value of the current induced in coil S is [Take $\pi^2 = 10$]

When a.c. source is connected across a pure capacitor, the correct phase relation between current and emf is shown in figure.

In series LCR circuit $R = 10\,\Omega$ and impedance is $30\,\Omega$. An r.m.s. voltage $210$ V, is applied across the circuit. The true power consumed in AC circuit is