The biological importance of the ozone layer is that:

The electromagnetic waves travel with a velocity

An electromagnetic wave of frequency $45 \text{ MHz}$ travels in free space along the $X$-axis. At some point and at some instant, the electric field has a maximum value of $750 \text{ NC}^{-1}$ along the $Y$-axis. The magnetic field at this position and time is

Write the standard equation for a plane electromagnetic wave traveling in the $x$-direction.

$A$ cube of unit volume contains $35 \times 10^7$ photons of frequency $10^{15} \text{ Hz}$. If the energy of all the photons is viewed as the average energy being contained in the electromagnetic waves within the same volume,then the amplitude of the magnetic field is $\alpha \times 10^{-9} \text{ T}$. Taking permeability of free space $\mu_0 = 4\pi \times 10^{-7} \text{ Tm/A}$,Planck's constant $h = 6 \times 10^{-34} \text{ Js}$ and $\pi = \frac{22}{7}$,the value of $\alpha$ is $.....$

Energy stored in electromagnetic oscillations is in the form of