JEE Main · 2026 · 28 Jan 2026 · Shift 1 · EM Waves

The electric field of a plane electromagnetic wave, travelling in an unknown non-magnetic medium is given by,
${\mathrm{E}}_{\mathrm{y}}=20\sin \left(3\times 10^6\mathrm{x}-4.5\times 10^{14}\mathrm{t}\right)\mathrm{V}/\mathrm{m}$
(where $\mathrm{x},\mathrm{t}$ and ot …

A laser beam has intensity of $4.0\times 10^{14}\mathrm{W}/{\mathrm{m}}^2$. The amplitude of magnetic field associated with beam is ______ T. (Take ${ϵ}_0=8.85\times 10^{-12}{\mathrm{C}}^2/{\mathrm{Nm}}^2$ and $\mathrm{c}=3\times 10^8\mathrm{m}/\mathrm{s}$)

An electromagnetic wave of frequency 100 MHz propagates through a medium of conductivity, $\sigma =10\mathrm{mho}/\mathrm{m}$. The ratio of maximum conducting current density to maximum displacement current density is ____ .

$[$ Take …

The equation of the electric field of an electromagnetic wave propagating through free space is given by :
$E=\sqrt{377}\sin \left(6.27\times 10^{3}t-2.09\times 10^{-5}x\right)$ N/C
The average power of the electromagnetic wave is $\left(\frac{1}{\alpha }\right)$ W/m${}^2$. T …

The ratio of speeds of electromagnetic waves in vacuum and a medium, having dielectric constant $k=3$ and permeability of $\mu =2{\mu }_0$, is (${\mu }_0=$ permeability of vacuum)

A plane electromagnetic wave is moving in free space with velocity c $=3\times 10^8\mathrm{m}/\mathrm{s}$ and its electric field is given as $\overrightarrow{\mathrm{E}}=54\sin (\mathrm{kz}-\omega \mathrm{t})\hat{\mathrm{j}}\mathrm{V}/\mathrm{m}$, where …