The electric field for a plane electromagnetic wave travelling in the $+y$ direction is shown. Consider a point where $\vec E$ is in the $+z$ direction. The $\vec B$ field is

The relative permittivity of distilled water is $81$. The velocity of light in it will be $....\times 10^{7} \text{ m/s}$. (Given $\mu_{r} = 1$) (in $.33$)

$A$ plane electromagnetic wave of frequency $50 \ MHz$ travels in free space. If the average energy densities in the electric field and magnetic field are $K_{E}$ and $K_{B}$ respectively,then the correct option in the following is

An electromagnetic wave of frequency $5\, GHz$ is travelling in a medium whose relative electric permittivity and relative magnetic permeability both are $2$. Its velocity in this medium is $\times 10^{7}\, m/s$.

This question has Statement-$1$ and Statement-$2$. Of the four choices given after the statements,choose the one that best describes the two statements.
Statement-$1$: Out of radio waves and microwaves,the radio waves undergo more diffraction.
Statement-$2$: Radio waves have a greater frequency compared to microwaves.

$A$ magnetic field vector in an electromagnetic wave is represented by $\vec{B} = B_0 \sin(2\pi vt - \frac{2\pi x}{\lambda}) \hat{j}$. Its associated electric field vector is . . . . . . .