The energy of electromagnetic wave in vacuum is given by the relation
$\frac{{{E^2}}}{{2{\varepsilon _0}}} + \frac{{{B^2}}}{{2{\mu _0}}}$
$\frac{1}{2}{\varepsilon _0}{E^2} + \frac{1}{2}{\mu _0}{B^2}$
$\frac{{{E^2} + {B^2}}}{c}$
$\frac{1}{2}{\varepsilon _0}{E^2} + \frac{{{B^2}}}{{2{\mu _0}}}$
A radar sends an electromagnetic signal of electric field $\left( E _{0}\right)=2.25\,V / m$ and magnetic field $\left( B _{0}\right)=1.5 \times 10^{-8}\,T$ which strikes a target on line of sight at a distance of $3\,km$ in a medium After that, a pail of signal $(echo)$ reflects back towards the radar vitli same velocity and by same path. If the signal was transmitted at time $t_{0}$ from radar. then after how much time (in $\times 10^{-5}\,s$) echo will reach to the radar?
The speed of electromagnetic wave in a medium (whose dielectric constant is $2.25$ and relative permeability is $4$ ) is equal to .......... $\times 10^8 \,m / s$
In a plane electromagnetic wave, the directions of electric field and magnetic field are represented by $\hat{ k }$ and $2 \hat{ i }-2 \hat{ j },$ respectively What is the unit vector along direction of propagation of the wave.
If $c $ is the speed of electromagnetic waves in vacuum, its speed in a medium of dielectric constant $K$ and relative permeability ${\mu _r}$ is
Ozone layer blocks the radiation of wavelength