The nature of electromagnetic waves is .......

The velocity of an electromagnetic wave in a medium is $2.5 \times 10^{8} \ m/s$. What is the dielectric constant of the medium?

The magnetic field in a plane electromagnetic wave is given by $\vec B = B_0 \sin(kx + \omega t) \hat j \ T$. The expression for the corresponding electric field will be (where $c$ is the speed of light).

Electromagnetic waves are emitted from a point source. The output power of the source is $1500 \, W$. The maximum value of the electric field at a point $3 \, m$ away from the source is ........ $V \, m^{-1}$.

Out of the following options,which one can be used to produce a propagating electromagnetic wave?

Choose the correct statement.