$A$ laser beam has intensity $2.1 \times 10^{15} \ W/m^2$. The amplitude of the magnetic field in the beam is approximately: (in $T$)

$A$ plane electromagnetic wave of frequency $25\; GHz$ is propagating in vacuum along the $z$-direction. At a particular point in space and time,the magnetic field is given by $\overrightarrow{B} = 5 \times 10^{-8} \hat{j}\; T$. The corresponding electric field $\overrightarrow{E}$ is (speed of light $c = 3 \times 10^{8}\; m/s$):

The electric field in an electromagnetic wave is given by $E = 50 \sin \frac{2 \pi}{\lambda}(ct - x) \ N/C$. Find the energy contained in a cylindrical region of cross-section $10 \ cm^2$ and length $50 \ cm$ along the $x$-axis.

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

The ratio of the magnitudes of the electric field and $10^8$ times the magnetic field of a plane electromagnetic wave is

$A$ plane electromagnetic wave has a frequency of $2.0 \times 10^{10} \ Hz$ and its energy density is $1.02 \times 10^{-8} \ J/m^3$ in vacuum. The amplitude of the magnetic field of the wave is close to $....nT$. (Given: $\frac{1}{4 \pi \varepsilon_0} = 9 \times 10^9 \ Nm^2/C^2$ and speed of light $c = 3 \times 10^8 \ m/s$)