The amplitude of the electric field in an electromagnetic wave is $1 \ V/m$. The frequency of the wave is $5 \times 10^{14} \ Hz$. The wave propagates along the $z$-axis. What is the average energy density of the electric field in $J/m^3$?

The electric field in an electromagnetic wave is given as $\vec{E} = 20 \sin \omega (t - \frac{x}{c}) \hat{j} \text{ N/C}$. Where $\omega$ and $c$ are the angular frequency and velocity of the electromagnetic wave,respectively. The energy contained in a volume of $5 \times 10^{-4} \text{ m}^3$ will be $..... \times 10^{-13} \text{ J}$. (Given $\varepsilon_0 = 8.85 \times 10^{-12} \text{ C}^2/\text{Nm}^2$)

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

When an $EM$ wave propagates through a vacuum,then:

For a plane electromagnetic wave,the electric field is given by $\vec{E} = 10 \cos(10^7t + kx) \hat{j} \text{ V/m}$. Where $t$ is in seconds and $x$ is in meters,then: $(i)$ The wavelength of this wave is $188.4 \text{ m}$. $(ii)$ The wave vector of this wave is $0.33 \text{ rad/m}$. $(iii)$ The amplitude of the electric field of this wave is $10 \text{ V/m}$. $(iv)$ This wave is propagating in the positive $X$-direction.

$A$ light bulb emits power of $800 \, W$. What is the maximum value of the magnetic field at a distance of $3.5 \, m$ from the bulb?