A plane electromagnetic wave travels in free space along the $x -$ direction. The electric field component of the wave at a particular point of space and time is $E =6\; Vm^{-1}$ along $y -$ direction. Its corresponding magnetic filed component, $B$ would be
$2 \times {10^{ - 8}}\,T$ along $z -$ direction
$6 \times {10^{ - 8}}\,T$ along $x -$ direction
$6 \times {10^{ - 8}}\,T$ along $z -$ direction
$2 \times {10^{ - 8}}\,T$ along $y -$ direction
A metal sample carrying a current along $X-$ axis with density $J_x$ is subjected to a magnetic field $B_z$ ( along $z-$ axis ). The electric field $E_y$ developed along $Y-$ axis is directly proportional io $J_x$ as well as $B_z$ . The constant of proportionality has $SI\, unit$.
The electric field of a plane electromagnetic wave varies with time of amplitude $2\, Vm^{-1}$ propagating along $z$ -axis. The average energy density of the magnetic field (in $J\, m^{-3}$) is
The electric field of an electromagnetic wave in free space is given by $\vec E$$=10 cos (10^7t+kx)$$\hat j$ $volt/m $ where $t$ and $x$ are in seconds and metres respectively. It can be inferred that
$(1)$ the wavelength $\lambda$ is $188.4\, m.$
$(2)$ the wave number $k$ is $0.33\,\, rad/m.$
$(4)$ the wave is propagating along $+x$ direction.
Which one of the following pairs of statements is correct ?
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
For a transparent medium relative permeablity and permittlivity, $\mu_{\mathrm{r}}$ and $\epsilon_{\mathrm{r}}$ are $1.0$ and $1.44$ respectively. The velocity of light in this medium would be,