$A$ plane electromagnetic wave of intensity $6 \, W/m^2$ strikes a small mirror of area $30 \, cm^2$,held perpendicular to the approaching wave. The momentum transmitted in $kg \cdot m/s$ by the wave to the mirror each second will be:

The electric field associated with an electromagnetic $(EM)$ wave in vacuum is given by $\vec{E} = \hat{i} 40 \cos (kz - 6 \times 10^{8} t)$,where $E$,$z$,and $t$ are in $V/m$,$m$,and $s$ respectively. The value of the wave vector $k$ is .... $m^{-1}$.

Light is an electromagnetic wave. Its speed in vacuum is given by the expression

The maximum electron density of the ionosphere layer in the morning is $10^{10} \ m^{-3}$. At noon,the maximum electron density increases to $2 \times 10^{10} \ m^{-3}$. What is the ratio of the critical frequency at noon to the critical frequency in the morning?

The magnetic field in a plane electromagnetic wave is given by $B = 3.01 \times 10^{-7} \sin(6.28 \times 10^2 x + 2.2 \times 10^{10} t) \, T$,where $x$ is in $cm$ and $t$ is in seconds. The wavelength of the given wave is ....... $cm$.

$A$ 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 nearly.......$V/m$