Electromagnetic Waves and Their Characteristics

An electromagnetic wave is travelling in a medium with a velocity $\overrightarrow{v}=v\widehat{i}$ . The electric field oscillations, of this electromagnetic wave wave, are along the y – axis.

(a) Identify the direction in which the magnetic field oscillations are taking place, of the electromagnetic wave wave.

(b) How are the magnitudes of the electric and magnetic fields in the electromagnetic wave related to each other?

A beam of light with intensity ${10}^{-3} \mathrm{N} {\mathrm{m}}^{-2}$ and cross sectional area $20 {\mathrm{cm}}^2$ is incident on a fully reflective surface at angle $45°$. Then the force exerted by the beam on the surface is

If the average power per unit area delivered by an electromagnetic wave is $9240 \mathrm{W} {\mathrm{m}}^{-2}$, then the amplitude of the oscillating magnetic field in EM wave is

A plane electromagnetic wave travels in free space along $z$- axis. At a particular point in space, the electric field along $x$-axis is $8.7 \mathrm{V} {\mathrm{m}}^{-1}$. The magnetic field along $\mathrm{y}$- axis is

The electric field $\left(E\right)$ and magnetic field $\left(B\right)$ of an electromagnetic wave passing through vacuum are given by
$E=E_0\sin \left(kx-\omega t\right)$
$B=B_0\sin \left(kx-\omega t\right)$
Then the correct statement among the following is

A light of intensity $12 \mathrm{W} {\mathrm{m}}^{-2}$ incidents on a black surface of area $4 {\mathrm{cm}}^2$. The radiation pressure on the surface is

The electric field of a plane electromagnetic wave propagating along the z-axis varies with time with an amplitude of $2\mathrm{ }\mathrm{V} {\mathrm{m}}^{-1}$. The average energy density of the magnetic field (in $\mathrm{J}\mathrm{ }{\mathrm{m}}^{-3}$) is :

Take: ${\mathrm{\epsilon }}_0=8.854\times {10}^{-12} \mathrm{F} {\mathrm{m}}^{-1}$

In a region of free space, the electric field at an instant of time is $\overrightarrow{\mathrm{E}}=\left(80\hat{\mathrm{i}}+32\hat{\mathrm{j}}-64\hat{\mathrm{k}}\right)\mathrm{V}·{\mathrm{m}}^{-1}$ and the magnetic field is $\overrightarrow{\mathrm{B}}=\left(0.2\hat{\mathrm{i}}+0.08\hat{\mathrm{j}}+0.29\hat{\mathrm{k}}\right)\mathrm{T}.$ The poynting vector is$\underline{ }$ Given magnetic permeability of free space is $4\pi \times {10}^{-7} \mathrm{H}·{\mathrm{m}}^{-1}.$

Assertion $\left(A\right):$ The colour of radiation does not change on passing through different media.

Reason $\left(R\right):$ The media do not absorb or emit colours.

Assertion $\left(A\right):$ Electromagnetic waves exert pressure, called radiation pressure. Reason $\left(R\right):$ This is because they carry energy.

Suppose that the electric field of an electromagnetic wave in vacuum is
$E=\left(3.1 \mathrm{N} {\mathrm{C}}^{-1}\right)\cos \left[\left(1.8 \mathrm{rad} {\mathrm{m}}^{-1}\right)y+\left(5.4\times {10}^6 \mathrm{rad} {\mathrm{s}}^{-1}\right)t\right]\hat{i}\text{. What is the wavelength }\lambda \text{ ? }$

A laser beam $(\mathrm{\lambda }=633 \mathrm{nm})$ has an average power of $3 \mathrm{mW}$. What will be the pressure exerted on a surface by this beam if the cross-sectional area is $3 {\mathrm{mm}}^2$? (Assume perfect reflection and normal incidence.)

The magnetic field in a travelling electromagnetic wave has a peak value of $20nT$. The peak value of electric field strength is:

Pick the incorrect statement for electromagnetic waves?

Consider an electromagnetic wave propagating in vacuum. Choose the correct statement:

The electric field component of a monochromatic radiation is given by $\overrightarrow{E}=2E_0\widehat{i}\cos kz\cos \omega t$ ,Its magnetic field $\overrightarrow{B}$ is then given by:

An earth-orbiting satellite has a solar energy collecting panel with total area $5\mathrm{ }{\mathrm{m}}^2$. If solar radiations are perpendicular and completely absorbed, the average force associated with the radiation pressure is
(Solar constant$=1.4\mathrm{ }\mathrm{k}\mathrm{W} {\mathrm{m}}^{-2}$)

Consider an electromagnetic wave propagating in a vacuum. Choose the correct statement.

Magnetic field in a plane electromagnetic wave is given by

$\overrightarrow{B}=B_0\sin \left(kx+\omega t\right)\widehat{\mathrm{j}} \mathrm{T}$
Expression for the corresponding electric field will be:
where $c$ is the speed of light.