The energy density of the electromagnetic wave in vacuum is given by the relation:

1. $\frac{1}{2}.\frac{E^2}{{\epsilon }_0}+\frac{B^2}{2{\mu }_0}$ 

2. $\frac{1}{2}{\epsilon }_0{E}^2+\frac{1}{2}{\mu }_0{B}^2$

3. $\frac{E^2+B^2}{C}$

4. $\frac{1}{2}{\epsilon }_0{E}^2+\frac{B^2}{2{\mu }_0}$

A lamp radiates power $P_0$ uniformly in all directions. The amplitude of electric field strength $E_0$ at a distance r from it is:

1. $E_0=\frac{P_0}{2{\mathrm{\pi \epsilon }}_0{\mathrm{cr}}^2}$

2. $E_0=\sqrt{\left\{\frac{P_0}{2{\mathrm{\pi \epsilon }}_{0}c{r}^2}\right\}}$

3. $E_0=\sqrt{\left\{\frac{P_0}{4{\mathrm{\pi \epsilon }}_0{\mathrm{cr}}^2}\right\}}$ 

4. $E_0=\sqrt{\left\{\frac{P_0}{8{\mathrm{\pi \epsilon }}_0{\mathrm{cr}}^{}}\right\}}$

The intensity of visible radiation at a distance of 1 m from a bulb of 100 W which converts only 5% of its power into light, is:

1. 0.4 W/m²

2. 0.5 W/m²

3. 0.1 W/m²

4. 0.01 W/m²

Which of the following statements about electromagnetic waves is/are correct:

1. A and B 
2. B and C
3. A, B and C
4. B only

Which of the following is not Maxwell's equation?
($\rho$= volume charge density, J = current density, m = pole strength, V = volume, S is closed surface, and C is closed loop)

The S.I. unit of displacement current is:
1. Henry
2. Coulomb
3. Ampere
4. Farad

If an electromagnetic wave going through a medium is given by; 
\(E=E_{0}sin\left ( kx-\omega t \right )\) and \(B=B_{0}sin\left ( kx-\omega t \right ),\) then:

Consider an electric charge oscillating with a frequency of 10 MHz. The radiation emitted will have a wavelength equal to:

Which of the following electromagnetic waves has minimum frequency?
1. Radio waves
2. Infrared waves
3. Microwaves
4. X-rays

A parallel plate capacitor consists of two circular plates each of radius 12 cm and separated by 5.0 mm. The capacitor is being charged by an external source. The charging current is constant and is equal to 0.15 A. The rate of change of the potential difference between the plates will be: