$A$ point source of electromagnetic radiation has an average output power of $800 \, W$. What is the maximum value of the electric field at a distance of $3.5 \, m$ from the source in $V/m$?

Find the direction of vibration of the electric field if the vibration of the magnetic field is in the positive $x-$ axis and the propagation of the electromagnetic wave is along the positive $y-$ axis.

$A$ plane electromagnetic wave of frequency $50\, MHz$ travels in free space along the positive $x-$ direction. At a particular point in space and time, $\vec E = 6.3\,\hat j\,V/m$. The corresponding magnetic field $\vec B$ at that point will be:

Given below are two statements:
Statement $I$: Electromagnetic waves are not deflected by electric and magnetic fields.
Statement $II$: The amplitude of the electric field and the magnetic field in electromagnetic waves are related to each other as $E_0 = \sqrt{\frac{\mu_0}{\varepsilon_0}} B_0$.
In the light of the above statements,choose the correct answer from the options given below:

An $EM$ wave from air enters a medium. The electric fields are $\overrightarrow {{E_1}} = {E_{01}}\hat x\cos[2\pi v(\frac{z}{c} - t)]$ in air and $\overrightarrow {{E_2}} = {E_{02}}\hat x\cos[k(2z - ct)]$ in medium,where the wave number $k$ and frequency $v$ refer to their values in air. The medium is nonmagnetic. If $\varepsilon_{r_1}$ and $\varepsilon_{r_2}$ refer to relative permittivities of air and medium respectively,which of the following options is correct?

The electric field associated with an electromagnetic wave propagating in a dielectric medium is given by $\vec{E} = 30(2 \hat{x} + \hat{y}) \sin \left[2 \pi \left(5 \times 10^{14} t - \frac{10^7}{3} z\right)\right] \text{V m}^{-1}$. Which of the following option$(s)$ is(are) correct?
[Given: The speed of light in vacuum,$c = 3 \times 10^8 \text{ m s}^{-1}$]
$(A)$ $B_x = -2 \times 10^{-7} \sin \left[2 \pi \left(5 \times 10^{14} t - \frac{10^7}{3} z\right)\right] \text{Wb m}^{-2}$.
$(B)$ $B_y = 2 \times 10^{-7} \sin \left[2 \pi \left(5 \times 10^{14} t - \frac{10^7}{3} z\right)\right] \text{Wb m}^{-2}$.
$(C)$ The wave is polarized in the $xy$-plane with a polarization angle $\theta = \tan^{-1}(0.5)$ with respect to the $x$-axis.
$(D)$ The refractive index of the medium is $2$.