The velocity of electromagnetic radiation in a medium of permittivity ${\varepsilon _0}$ and permeability ${\mu _0}$ is given by
$\sqrt {\frac{1}{{{\mu _0}{\varepsilon _0}}}} $
$\;\sqrt {\frac{{{\mu _0}}}{{{\varepsilon _0}}}} $
$\;\sqrt {\frac{{{\varepsilon _0}}}{{{\mu _0}}}} $
$\;\sqrt {{\mu _0}{\varepsilon _0}} $
$TV$ waves have a wavelength range of $1-10 \,meter$. Their frequency range in $MHz$ is
In an electromagnetic wave the electric field vector and magnetic field vector are given as $\vec{E}=E_{0} \hat{i}$ and $\vec{B}=B_{0} \hat{k}$ respectively. The direction of propagation of electromagnetic wave is along.
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
A laser beam can be focussed on an area equal to the square of its wavelength A $He-Ne$ laser radiates energy at the rate of $1\,mW$ and its wavelength is $632.8 \,nm$. The intensity of focussed beam will be
Given below are two statements:
Statement $I$: Electromagnetic waves carry energy as they travel through space and this energy is equally shared by the electric and magnetic fields.
Statement $II$: When electromagnetic waves strike a surface, a pressure is exerted on the surface.In the light of the above statements, choose the most appropriate answer from the options given below: