If the magnetic field of a plane electromagnetic wave is given by $B = 5 \times 10^{-6} \sin (0.6 \times 10^2 x + 0.5 \times 10^{10} t)$,then the speed of the wave is

If ${\varepsilon _0}$ and ${\mu _0}$ are respectively the electric permittivity and the magnetic permeability of free space,and ${\varepsilon}$ and ${\mu}$ are the corresponding quantities in a medium,the refractive index of the medium is:

The average value of electric energy density in an electromagnetic wave is. [where $E_0$ is peak value]

The relationship between the amplitude of the electric field $(E_0)$ and the magnetic field $(B_0)$ in an electromagnetic wave is given by:

The condition under which a microwave oven heats up a food item containing water molecules most efficiently is

$A$ plane electromagnetic wave travelling along the $X-$ direction has a wavelength of $3\, mm$. The variation in the electric field occurs in the $Y-$ direction with an amplitude of $66\, Vm^{-1}$. The equations for the electric and magnetic fields as a function of $x$ and $t$ are respectively: