The electromagnetic waves travel in a medium at a speed of $2.0 \times 10^{8} \ m/s$. The relative permeability of the medium is $1.0$. The relative permittivity of the medium will be (in $.25$)

$A$ microwave oven heats food containing water molecules very efficiently under which of the following conditions?

Energy stored in electromagnetic oscillations is in the form of

$A$ radiation is emitted by a $1000 \, W$ bulb and it generates an electric field and magnetic field at point $P$, placed at a distance of $2 \, m$. The efficiency of the bulb is $1.25 \%$. The value of the peak electric field at $P$ is $x \times 10^{-1} \, V/m$. The value of $x$ is (rounded off to the nearest integer).
[Take $\varepsilon_{0} = 8.85 \times 10^{-12} \, C^2 N^{-1} m^{-2}, c = 3 \times 10^8 \, m/s$]

$X$-rays,gamma rays and microwaves travelling in vacuum have

For an electromagnetic wave,the electric field is given by $E_x = 36 \sin(1.20 \times 10^7 z - 3.6 \times 10^{15} t) \ V/m$. What is the intensity of the electric field in $W/m^2$?