The pressure exerted by an electromagnetic wave of intensity $I (watts/m^2)$ on a nonreflecting surface is [$c$ is the velocity of light]
$Ic$
$I{c^2}$
$I/c$
$I/{c^2}$
The average value of electric energy density in an electromagnetic wave is :
The magnetic field of a beam emerging from a filter facing a floodlight is given by B${B_0} = 12 \times {10^{ - 8}}\,\sin \,(1.20 \times {10^7}\,z - 3.60 \times {10^{15}}t)T$. What is the average intensity of the beam ?
An electromagnetic wave is represented by the electric field $\vec E = {E_0}\hat n\,\sin \,\left[ {\omega t + \left( {6y - 8z} \right)} \right]$. Taking unit vectors in $x, y$ and $z$ directions to be $\hat i,\hat j,\hat k$ ,the direction of propogation $\hat s$, is
$TV$ waves have a wavelength range of $1-10 \,meter$. Their frequency range in $MHz$ is
The electric field of a plane electromagnetic wave varies with time of amplitude $2\, Vm^{-1}$ propagating along $z$ -axis. The average energy density of the magnetic field (in $J\, m^{-3}$) is