If a source of power $4\ kW$ produces $10^{20}$ photons/second , the radiation belongs to a part of the spectrum called

The electric and the magnetic field, associated with an e.m. wave, propagating along the $+\, z-$axis, can be represented by

The ratio of the magnitude of the magnetic field and electric field intensity of a plane electromagnetic wave in free space of permeability $\mu_0$ and permittivity $\varepsilon_0$ is (Given that $c$ - velocity of light in free space)

Energy stored in electromagnetic oscillations is in the form of

Radiations of intensity $0.5\,\,W/{m^2}$ are striking a metal plate. The pressure on the plate is

A monochromatic beam of light has a frequency $v = \frac{3}{{2\pi }} \times {10^{12}}\,Hz$ and is propagating along the direction $\frac{{\hat i + \hat j}}{{\sqrt 2 }}$. It is polarized along the $\hat k$ direction. The acceptable form for the magnetic field is