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 $............J$
$48 \times 10^{3}$
$10 \times 10^{3}$
$12 \times 10^{3}$
$24 \times 10^{3}$
A carbon dioxide laser emits sinusoidal electro-magnetic wave that travels in vacuum in the negative $x-$ direction. The wavelength is $10.6\,\mu $ and $\vec E$ fields is parallel to $z-$ axis, with $E_{max} = 1.5 \times 10^6\, M\, v/m$. Then vector equations for $\vec E$ and $\vec B$ as a function of time and position are
An electromagnetic wave with frequency $\omega $ and wavelength $\lambda $ travels in the $+ y$ direction . Its magnetic field is along $+\, x-$ axis. The vector equation for the associated electric field ( of amplitude $E_0$) is
If the magnetic field in a plane electromagnetic wave is given by
$\overrightarrow{\mathrm{B}}=3 \times 10^{-8} \sin \left(1.6 \times 10^{3} \mathrm{x}+48 \times 10^{10} \mathrm{t}\right) \hat{\mathrm{j}}\; \mathrm{T}$
then what will be expression for electric field?
If $E$ and $B$ denote electric and magnetic fields respectively, which of the following is dimensionless
Show that the radiation pressure exerted by an $EM$ wave of intensity $I$ on a surface kept in vacuum is $\frac{I}{c}$.