Electromagnetic waves practice · Mixed difficulty

The S.I. unit of displacement current is:

You are given a $2 \mu \mathrm{F}$ parallel plate capacitor. How would you establish an instantaneous displacement current of $1 \mathrm{~mA}$ in the space between its plates?

If electric field in an electromagnetic wave is given by $E=6 \times 10^6 \sin \left(2 \pi f t-\frac{2 \pi}{\lambda} x\right) \frac{\mathrm{V}}{\mathrm{m}}$. The peak value of magnetic field in the region is

Assertion: The velocity of electromagnetic waves depends on
electric and magnetic properties of the medium
Reason: Velocity of electromagnetic waves in free space is
constant

The electromagnetic wave having the shortest wavelength is

Given below are two statements:
Statement I: Electromagnetic waves carry energy
as they travel through space and this energy is
equally shared by the electric and magnetic fields
Statement II: When electromagnetic waves strike
a surface, a pressure is exerted on the surface
In the light of the above statements, choose the
most appropriate answer from the options given
below

The range of frequency allotted for FM radio is

Pick out the longest wavelength from the following types of radiations

Assertion: The gyrating electron can be source of EMW.

Reason: The electron in circular motion is accelerated motion.

In an electromagnetic wave, the direction of the magnetic field induction $\vec{B}$ is

The electromagnetic waves generally used in the purification of water are

Which of the following electromagnetic wave play an important role in maintaining the earth’s warmth or average temperature through the greenhouse effect?

Find the displacement current developed in the space between the plates of parallel plate capacitor of capacity $2 \mu \mathrm{F}$ when voltage is changing at a rate of $10^6 \mathrm{Vs}^{-1}.$

Which rays are not part of electromagnetic spectrum?

The part of the spectrum of the electromagnetic radiation used to cook food is

The wave function (in S.I units) for an electromagnetic wave is given as $- \psi \left( {X,t} \right) = {10^3}\sin \pi \left( {3 \times {{10}^6}X - 9 \times {{10}^{14}}t} \right)$. The speed of wave is :

The charge of a parallel plate capacitor is varying as $q = {q_0}\sin 2\pi ft$. The plates are very large and close together (area$= A$, separation$= d$). Neglecting edge effects, the displacement current through the capacitor is

The electromagnetic waves travel with a velocity

Find the values of magnetic field between plates of capacitor at distance $1 \mathrm{~m}$ from centre where electric field varies by $10^{10}$ volt $/ \mathrm{m} / \mathrm{s}$.

Assertion: During discharging there is magneticfield between plates of capacitor.

Reason : Time varying electric field produces magnetic field.

Which of the following statements about electromagnetic waves is/are correct?

(1) X-rays in vacuum travel faster than light waves in vacuum.

(2) The energy of X-ray photon is greater than that of a light photon

(3) Light can be polarised but X-ray cannot.

A radar sends the waves towards a distant object and receives the signal reflected by object. These waves are

The maximum electric field in a plane electromagnetic wave is $600 \mathrm{~NC}^{-1}$. The wave is going in the $x$-direction and the electric field is in the $y$-direction. Find the maximum magnetic field in the wave and its direction.

What physical quantity is the same for $\mathrm{X}$-rays of wavelength ${10^{-10}} \mathrm{~m}$, red light of wavelength $6800 ~\mathop {\text{A}}\limits^ \circ$, and radiowaves of wavelength $500 \mathrm{~m}$?

An electromagnetic wave is propagating along $\mathrm{Y}$-axis. Then

$50\mathrm{ W/}{\mathrm{m}^2}$ energy density of sunlight is normally incident on the surface of a solar panel. Some part of incident energy (25%) is reflected from the surface and the rest is absorbed. The force exerted on $\mathrm{1 }{\mathrm{m}^\mathrm{2}}$ surface area will be close to $(c = 3 \times {10^8}{\rm\,\,{m/s)}}$

For an electromagnetic wave traveling in free space

An EM wave radiates outwards from a dipole antenna with $E_0$ as the amplitude of its electric field vector. The electric field $E_0$ which transports significant energy from the source falls off as

Assertion: A changing electric-field produces a magnetic field.

Reason: A changing magnetic field produces an electric field.

A new system of units is evolved in which the values of ${\mu _0}$ and ${\varepsilon _0}$ are 2 and 8 respectively. Then the speed of light in this system will be