The electric field of a plane electromagnetic wave is given by

$\overrightarrow{\mathrm{E}}=\mathrm{E}_{0} \frac{\hat{\mathrm{i}}+\hat{\mathrm{j}}}{\sqrt{2}} \cos (\mathrm{kz}+\omega \mathrm{t})$ At $\mathrm{t}=0,$ a positively charged particle is at the point $(\mathrm{x}, \mathrm{y}, \mathrm{z})=\left(0,0, \frac{\pi}{\mathrm{k}}\right) .$ If its instantaneous velocity at $(t=0)$ is $v_{0} \hat{\mathrm{k}},$ the force acting on it due to the wave is

Light with an average flux of $20\, W / cm ^{2}$ falls on a non-reflecting surface at normal incidence having surface area $20\, cm ^{2} .$ The energy recelved by the surface during time span of $1$ minute is $…………J$

A plane electromagnetic wave of frequency $25 \;MHz$ travels in free space along the $x$ -direction. At a particular point in space and time, $E = 6.3\,\hat j\;\,V/m$. What is $B$ at this point? 

The electric and the magnetic field, associated with an e.m. wave, propagating along the $+\, z-$axis, can be represented by

If frequency of electromagnetic wave is $60 \mathrm{MHz}$ and it travels in air along $\mathrm{z}$ direction then the corresponding electric and magnetic field vectors will be mutually perpendicular to each other and the wavelength of the wave (in $\mathrm{m}$ ) is :