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
${H_o} = {E_o}$
${H_o} = \frac{{{E_o}}}{C}$
${H_o} = {E_o}\,\sqrt {\frac{{{\mu _o}}}{{{\varepsilon _o}}}} $
${H_o} = {E_o}\,\sqrt {\frac{{{\varepsilon _o}}}{{{\mu _o}}}} $
About $5 \%$ of the power of a $100\; W$ light bulb is converted to visible radiation. What is the average intensity of visible radiation
$(a)$ at a distance of $1 \;m$ from the bulb?
$(b)$ at a distance of $10\; m ?$ Assume that the radiation is emitted isotropically and neglect reflection.
For a plane electromagnetic wave propagating in $x$-direction, which one of the following combination gives the correct possible directions for electric field $(E)$ and magnetic field $(B)$ respectively?
The ratio of amplitude of magnetic field to the amplitude of electric field for an electromagnetic wave propagating in vacuum is equal to
Select the correct statement from the following
An electromagnetic wave with frequency $\omega $ and wavelength $\lambda $ travels in the $+y$ direction. Its magnetic field is along $+x$ axis. The vector equation for the associated electric field (of amplitude $E_0$) is