Write equation of energy density of electromagnetic waves.

A light wave is incident normally on a glass slab of refractive index $1.5$. If $4\%$ of light gets reflected and the amplitude of the electric field of the incident light is $30\, V/m$, then the amplitude of the electric field for the wave propagating in the glass medium will be…….$ V/m$

The speed of electromagnetic radiation in vacuum is

If electromagnetic wave is propagating in $x-$ direction and electric and magnetic field are in $y$ and $z-$ direction respectively then write equation of $Ey$ and $Bz$. 

Electric field in a plane electromagnetic wave is given by ${E}=50 \sin \left(500 {x}-10 \times 10^{10} {t}\right) \,{V} / {m}$ The velocity of electromagnetic wave in this medium is :

(Given ${C}=$ speed of light in vacuum)