Newton's laws can be applied to mechanical waves propagating in elastic media. Can they be applied to electromagnetic waves also?

The velocity of an electromagnetic wave is in the direction of

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:

An electromagnetic wave has an electric field given by the expression (in Cartesian coordinates) $\vec E(x,t) = 6.0\,\cos(1 \times 10^7x - 3 \times 10^{15}t)\hat z$. What is the direction of the magnetic field at time $t = 0$ and position $x = 0$?

The electric field of a plane electromagnetic wave propagating along the $x$-direction in vacuum is $\overrightarrow{E} = E_{0} \hat{j} \cos(\omega t - kx)$. The magnetic field $\overrightarrow{B}$ at the moment $t = 0$ is:

Electromagnetic waves of frequency $8.196 \times 10^6 \ Hz$ are propagating from a source. What is the wavelength of these electromagnetic waves in $cm$?