The equation of the electric field of an electromagnetic wave propagating through free space is given by:
$E = \sqrt{377} \sin(6.27 \times 10^3 t - 2.09 \times 10^{-5} x) \text{ N/C}$.
The average power (intensity) of the electromagnetic wave is $\left(\frac{1}{\alpha}\right) \text{ W/m}^2$. The value of $\alpha$ is . . . . . . .
(Take $\sqrt{\frac{\mu_0}{\varepsilon_0}} = 377$ in $SI$ units)

The power radiated from a linear antenna of length $l$ is proportional to (Given,$\lambda =$ wavelength of the wave):

If $11 \%$ of the power of a $200 \ W$ bulb is converted to visible radiation,then the intensity of the light at a distance of $100 \ cm$ from the bulb is (in $W \ m^{-2}$)

In an electromagnetic wave,the electric field and magnetising field are $100\,V\,m^{-1}$ and $0.265\,A\,m^{-1}$ respectively. The maximum energy flow is.......$W\,m^{-2}$.

$A$ radar sends an electromagnetic signal with an electric field $E_{0} = 2.25\,V/m$ and a magnetic field $B_{0} = 1.5 \times 10^{-8}\,T$,which strikes a target on the line of sight at a distance of $3\,km$ in a medium. After that,a part of the signal (echo) reflects back towards the radar with the same velocity and along the same path. If the signal was transmitted at time $t_{0}$ from the radar,then after how much time (in $\times 10^{-5}\,s$) will the echo reach the radar?

The energies required to set up in a cube of side $10 \ cm$,$(a)$ a uniform electric field of $10^7 \ V \ m^{-1}$ and $(b)$ a uniform magnetic field of $0.25 \ Wb \ m^{-2}$,are respectively about $(\mu_0 = 4\pi \times 10^{-7} \ H \ m^{-1}, \epsilon_0 = 8.9 \times 10^{-12} \ F \ m^{-1})$.