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

The electric field of an electromagnetic wave in free space is represented as $\vec{E} = E_0 \cos(\omega t - kz) \hat{i}$. The corresponding magnetic induction vector will be:

Assertion $(A):$ $A$ charge moving in a circular orbit can produce electromagnetic waves.
Reason $(R):$ The source of electromagnetic waves should be in accelerated motion.

The energy of an electromagnetic wave contained in a small volume oscillates with

If $\vec E$ and $\vec B$ represent the electric and magnetic field vectors of an electromagnetic wave,then the direction of propagation of the electromagnetic wave is in the direction of

The radiation energy emitted per second by a point source is $100 \,W$. If the efficiency of the source is $4 \%$, then the rms value of the electric field at a distance of $2 \,m$ is [use $\frac{1}{4 \pi \varepsilon_0}=9 \times 10^9$ in $SI$ units].