The ratio of the magnitudes of the electric field to the magnetic field of an electromagnetic wave is of the order of

In an $EM$ wave propagating along the $X-$ direction,the magnetic field oscillates at a frequency of $3 \times 10^{10} \, Hz$ along the $Y-$ direction and has an amplitude of $10^{-7} \, T$. The expression for the electric field will be:

For a given electromagnetic wave,the magnitude of the electric field is $6.6 \,V \,m^{-1}$ at a point in space. The magnitude of the magnetic field at this point is . . . . . . $T$.

The electric field in a plane electromagnetic wave is given by $E = 50 \sin(500x - 10 \times 10^{10}t) \, V/m$. The velocity of the electromagnetic wave in this medium is: (Given $C = \text{speed of light in vacuum}$)

The electric fields of two plane electromagnetic waves in vacuum are given by $\overrightarrow{E}_{1}=E_{0} \hat{j} \cos (\omega t-kx)$ and $\overrightarrow{E}_{2}=E_{0} \hat{k} \cos (\omega t-ky)$. At $t=0$,a particle of charge $q$ is at the origin with a velocity $\overrightarrow{v}=0.8 c \hat{j}$ ($c$ is the speed of light in vacuum). The instantaneous force experienced by the particle is:

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