A lamp emits monochromatic green light uniformly in all directions. The lamp is 3% efficient in converting electrical power to electromagnetic waves and consumes 100 W of power. The amplitude of the electric field associated with the electromagnetic radiation at a distance of 5 m from the lamp will be

(1) 1.34 V/m

(2) 2.68 V/m

(3) 4.02 V/m

(4) 5.36 V/m

A parallel plate capacitor consists of two circular plates each of radius \(2~\text{cm}\), separated by a distance of \(0.1~\text{mm}\). If the voltage across the plates is varying at the rate of $\mathrm{}$\(5\times10^{13}~\text{V/s}\), then the value of displacement current is:
1. \(5.50~\text{A}\)
2. \(5.56\times 10^{2}~\text{A}\)
3. \(5.56\times 10^{3}~\text{A}\)
4. \(2.28\times 10^{4}~\text{A}\)

In an electromagnetic wave:

For any E.M. wave if E = 100 V/m and B = 0.265 Then the rate of maximum energy flow per unit area is:

(1) $3.33\times {10}^{-5} J/m^2$

(2) 26.5 W/$m^2$

(3) $3\times {10}^8 J/m^2$

(4) None of these

A variable frequency AC source is connected to a capacitor. Then on increasing the frequency

(1) Both conduction current and displacement current will increase

(2) Both conduction current and displacement current will decrease

(3) Conduction current will increase and displacement will decrease

(4) Conduction current will decrease and displacement current will increase

Instantaneous displacement current of 2.0 A is set up in the space between two parallel plates of 1 $\mu F$ capacitor. The rate of change in potential difference across the capacitor is-

(1) $3\times {10}^6 V/s$

(2) $4\times {10}^6 V/s$

(3) $2\times {10}^6 V/s$

(4) none of these

Which of the following have zero average value in a plane electromagnetic wave?

(1) electric field

(2) magnetic field

(3) magnetic & electric field both

(4) none of these

In a plane electromagnetic wave propagating in space has an electric field of amplitude $9\times {10}^3$ V/m, then the amplitude of the magnetic field is

(1) $2.7\times {10}^{12} T$

(2) $9.0\times {10}^{-3} T$

(3) $3.0\times {10}^{-4} T$

(4) $3.0\times {10}^{-5} T$

A radiowave has a maximum magnetic field induction of ${10}^{-4}$ T on arrival at a receiving antenna. The maximum electric field intensity of such a wave is

(1) zero

(2) $3\times {10}^4 V/m$

(3) $5.8\times {10}^{-9} V/m$

(4) $3.3\times {10}^{13 } V/m$

A capacitor is having a capacity of 2 pF. The electric potential across the capacitor is changing with a value of ${10}^{12}$ V/s. The displacement current is :

(1) 2 A

(2) 3 A

(3) 6 A

(4) 9 A