The direction of the Poynting vector represents:

The magnetic field of an $\text{E.M.}$ wave is given by $\overrightarrow{ B }=\left(\frac{\sqrt{3}}{2} \hat{ i }+\frac{1}{2} \hat{ j }\right) 30 \sin \left[\omega\left( t -\frac{ z }{ c }\right)\right]$ ($\text{S.I.}$ units). The corresponding electric field in $\text{S.I.}$ units is:

The dimensions of $\frac{1}{{\mu _0}{\varepsilon _0}}$ are .......... .

In a plane electromagnetic wave,the electric field oscillates with a frequency $2 \times 10^{10} \,s^{-1}$ and amplitude $40 \,Vm^{-1}$. The energy density due to the electric field is (given $\varepsilon_0 = 8.85 \times 10^{-12} \,Fm^{-1}$):

$A$ carbon dioxide laser emits a sinusoidal electromagnetic wave that travels in a vacuum in the negative $x-$ direction. The wavelength is $10.6\,\mu m$ and the $\vec E$ field is parallel to the $z-$ axis,with $E_{max} = 1.5 \times 10^6\, V/m$. Then the vector equations for $\vec E$ and $\vec B$ as a function of time and position are:

The velocity of electromagnetic radiation in a medium of permittivity $\varepsilon_{0}$ and permeability $\mu_{0}$ is given by