A plane electromagnetic wave of wave intensity $6\, W/ m^2$ strikes a small mirror area $40 cm^2$, held perpendicular to the approaching wave. The momentum transferred by the wave to the mirror each second will be
$6.4 \times {10^{ - 7}}kg - m/{s^2}$
$4.8 \times {10^{ - 8}}kg - m/{s^2}$
$3.2 \times {10^{ - 9}}kg - m/{s^2}$
$1.6 \times {10^{ - 10}}kg - m/{s^2}$
The electric field part of an electromagnetic wave in vacuum is
$E = 3.1\,NC^{-1}\,cos\,[\,(1.8\,rad\,m^{-1})\,y + (5.4\times 18^8\,rad\,s^{-1})\,t\,]\,\hat i$
The wavelength of this part of electromagnetic wave is......$m$
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
A plane electromagnetic wave of frequency $28 \,MHz$ travels in free space along the positive $x$-direction. At a particular point in space and time, electric field is $9.3 \,V / m$ along positive $y$-direction. The magnetic field (in $T$ ) at that point is
Which scientist discarded postulate of ether?
Pointing vectors $\vec S$ is defined as a vector whose magnitude is equal to the wave intensity and whose direction is along the direction of wave propagation. Mathematically, it is given by $\vec S = \frac{1}{{{\mu _0}}}(\vec E \times \vec B)$. Show the nature of $\vec S$ vs $t$ graph.