Electromagnetic waves travel in a medium with a speed of $1.5 \times 10^8 \ m/s$. The relative permeability of the medium is $2.0$. The relative permittivity will be:

The electric field in an electromagnetic wave is given as $\vec{E} = 20 \sin \omega (t - \frac{x}{c}) \hat{j} \text{ N/C}$. Where $\omega$ and $c$ are the angular frequency and velocity of the electromagnetic wave,respectively. The energy contained in a volume of $5 \times 10^{-4} \text{ m}^3$ will be $..... \times 10^{-13} \text{ J}$. (Given $\varepsilon_0 = 8.85 \times 10^{-12} \text{ C}^2/\text{Nm}^2$)

Suppose that the intensity of a laser is $\left(\frac{315}{\pi}\right) \ W/m^2$. The $rms$ electric field,in units of $V/m$,associated with this source is close to the nearest integer. Given: $\epsilon_0 = 8.86 \times 10^{-12} \ C^2 N^{-1} m^{-2}$ and $c = 3 \times 10^8 \ m/s$.

If the average power per unit area delivered by an electromagnetic wave is $9240 \ W \ m^{-2}$,then the amplitude of the oscillating magnetic field in the $EM$ wave is: (in $\mu T$)

The ratio of the magnitudes of the electric field to the magnetic field of an electromagnetic wave is of the order of

Assertion $(A)$: Electromagnetic waves exert pressure,called radiation pressure.
Reason $(R)$: This is because they carry energy.