The $rms$ value of the electric field of the light coming from the Sun is $720 \; N/C$. The average total energy density of the electromagnetic wave is

$A$ point source of $100\,W$ emits light with $5\%$ efficiency. At a distance of $5\,m$ from the source,the intensity produced by the electric field component is:

The electric field of an electromagnetic wave in free space is given by $\vec E = 10 \cos (10^7 t + kx) \hat j \, V/m$,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 $0.33 \, rad/m$.
$(3)$ The wave amplitude is $10 \, V/m$.
$(4)$ The wave is propagating along $+x$ direction.
Which one of the following pairs of statements is correct?

The oscillating electric and magnetic field vectors of an electromagnetic wave are along

The magnetic field in a plane electromagnetic wave is given by $B_y = (3.5 \times 10^{-7}) \sin (1.5 \times 10^3 x + 0.5 \times 10^{11} t) \ T$. The corresponding electric field will be:

The mean intensity of radiation on the surface of the Sun is about $10^{8} \ W/m^2$. The $rms$ value of the corresponding magnetic field is closest to