An em wave is propagating in a medium with a velocity $\vec v =v\hat i.$ The instantaneous oscillating electric field of this em wave is along $+y$ axis. Then the direction of oscillating magnetic field of the em wave will be along

In the $EM$ wave the amplitude of magnetic field $H_0$ and the amplitude of electric field $E_o$ at any place are related as

Which scientist discarded postulate of ether? 

An infinitely long thin wire carrying a uniform linear static charge density $\lambda $ is placed along the $z-$ axis (figure). The wire is set into motion along its length with a uniform velocity $V = v{\hat k_z}$. Calculate the pointing vector $S = \frac{1}{{{\mu _0}}}(\vec E \times \vec B)$ .

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 $Bz$. 

The mean intensity of radiation on the surface of the Sun is about $10^{8}\,W/m^2.$ The $rms$ value of the corresponding magnetic field is closet to