A coil has 100 turns, each of area $0.05 \mathrm{~m}^2$ and total resistance $1.5 \Omega$. It is inserted at an instant in a magnetic field of 90 mT , with its axis parallel to the field. The charge induced in the coil at that instant is

You are required to design an air-filled solenoid of inductance 0.016 H having a length 0.81 m and radius 0.02 m . The number of turns in the solenoid should be

A voltage $v=v_0 \sin \omega t$ applied to a circuit drives a current $i=i_0 \sin (\omega t+\phi)$ in the circuit. The average power consumed in the circuit over a cycle is

The given diagram exhibits the relationship between the wavelength of the electromagnetic waves and the energy of photon associated with them. The three points $\mathbf{P}, \mathbf{Q}$ and $\mathbf{R}$ marked on the diagram may correspond respectively to