An electromagnetic wave of wavelength $2 \times 10^{-10} \,m$ passes from vacuum into a dielectric medium of relative permittivity $4$. Then its wavelength will be

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

The electric field in an electromagnetic wave is given by $E = 56.5 \sin \omega(t - x/c) \; NC^{-1}$. Find the intensity of the wave if it is propagating along the $x$-axis in free space. (Given $\varepsilon_{0} = 8.85 \times 10^{-12} \; C^{2} N^{-1} m^{-2}$ and $c = 3 \times 10^{8} \; m/s$)

If the amplitude of the magnetic field in a travelling plane electromagnetic wave is $2.2 \times 10^{-4} \ T$,then the intensity of the wave is nearly

In a plane electromagnetic wave,$U_E$ and $U_B$ are the average energy densities of the electric field and magnetic field,respectively. Then,which of the following is the correct option?

An electromagnetic wave is propagating in vacuum along $-\hat{j}$ direction. The magnetic field of the wave is given by $\vec{B} = (2 \times 10^{-8}) \cos [\pi \times 10^{15}(t + \frac{y}{c})] \hat{k} \text{ T}$. The electric field $\vec{E}$ of this wave is $(c = \text{speed of light})$