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

Suppose that the electric field of an electromagnetic wave in vacuum is $E = (3.1 \text{ NC}^{-1}) \cos [(1.8 \text{ rad m}^{-1}) y + (5.4 \times 10^6 \text{ rad s}^{-1}) t] \hat{i}$. What is the wavelength $\lambda$ (in $\text{ m}$)?

Electromagnetic waves are incident normally on a perfectly reflecting surface having surface area $A$. If $I$ is the intensity of the incident electromagnetic radiation and $c$ is the speed of light in vacuum,the force exerted by the electromagnetic wave on the reflecting surface is

For a plane electromagnetic wave,the magnetic field at a point $x$ and time $t$ is $\overrightarrow{ B }( x , t ) = [1.2 \times 10^{-7} \sin (0.5 \times 10^{3} x + 1.5 \times 10^{11} t) \hat{ k }] \text{ T}$. The instantaneous electric field $\overrightarrow{ E }$ corresponding to $\overrightarrow{ B }$ is: (speed of light $c = 3 \times 10^{8} \text{ m/s}$)

The refractive index of the ionosphere is ........

The oscillating electric and magnetic vectors of an electromagnetic wave are oriented along