Electromagnetic Waves
Practice Questions
MCQ (Single Correct Answer)
1
For plane electromagnetic waves propagating in the positive $z$-direction. The combination which gives the correct possible direction for $\mathbf{E}$ and $\mathbf{B}$ fields respectively is
AP EAPCET 2024 - 23th May Morning Shift
2
Size of the antenna for a carrier wave of frequency 3 MHz is
AP EAPCET 2024 - 23th May Morning Shift
3
The radiation of energy $E$ falls normally on a perfectly reflecting surface. The momentum transferred to the surface is
AP EAPCET 2024 - 22th May Evening Shift
4
The structure of solids is investigated by using
AP EAPCET 2024 - 22th May Morning Shift
5
The rms value of the electric field of an electromagnetic wave emitted by a source is $660 \mathrm{NC}^{-1}$. The average energy density of the electromagnetic wave is
AP EAPCET 2024 - 21th May Evening Shift
6
A transmitter of power 10 kW emits radio waves of wavelength 500 m . The number of photons emitted por second by the transmitter of the order of
AP EAPCET 2024 - 21th May Evening Shift
7
Which of the following produces electromagnetic waves?
AP EAPCET 2024 - 21th May Morning Shift
8
The average value of electric energy density in an electromagnetic wave is where $E_0$ is peak value
AP EAPCET 2024 - 20th May Morning Shift
9
An electromagnetic wave travel in a medium with a speed of $2 \times 10^8 \mathrm{~ms}^{-1}$. The relative permeability of the medium is 1 . Then, the relative permittivity is
AP EAPCET 2024 - 19th May Evening Shift
10
A message signal of 3 kHz is used to modulate a carric signal frequency 1 MHz , using amplitude modulation. The upper side band frequency and band width respectively are
AP EAPCET 2024 - 19th May Evening Shift
11
The solar radiation is
AP EAPCET 2024 - 18th May Morning Shift
12

The magnetic field in a plane electromagnetic wave is given as $$\mathbf{B}=\left(3 \times 10^{-7} \mathrm{~T}\right) \sin \left(3 \times 10^4 x+9 \times 10^{12} t\right) \hat{j}$$

The electric field of this wave is given as

AP EAPCET 2022 - 5th July Morning Shift
13

Frequencies in the UHF range normally propagate by means of

AP EAPCET 2022 - 5th July Morning Shift
14

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

AP EAPCET 2022 - 4th July Evening Shift
15

The electric field $$(E)$$ and magnetic field $$(B)$$ of an electromagnetic wave passing through vacuum are given by

$$\begin{aligned} & E=E_0 \sin (k x-\omega t) \\ & B=B_0 \sin (k x-\omega t) \end{aligned}$$

Then the correct statement among the following is

AP EAPCET 2022 - 4th July Evening Shift
16

A carrier wave is used to transmit a message signal. If the peak voltage of modulating signal and carrier signal are increased by $$1 \%$$ and $$3 \%$$ respectively, the modulation index is changed by

AP EAPCET 2022 - 4th July Evening Shift
17

A plane electromagnetic wave travels in free space along $$Z$$-axis. At a particular point in space, the electric field along $$X$$-axis is $$8.7 \mathrm{~Vm}^{-1}$$. The magnetic field along $$Y$$-axis is

AP EAPCET 2022 - 4th July Morning Shift
18

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

AP EAPCET 2022 - 4th July Morning Shift
19

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

AP EAPCET 2022 - 4th July Morning Shift
20

The maximum number of TV signals, that can be transmitted along a co-axial cable is

AP EAPCET 2022 - 4th July Morning Shift
21

The electric and the magnetic fields associated with an electromagnetic wave propagating along the $$z$$-axis, can be represented by

AP EAPCET 2021 - 20th August Morning Shift
22

The magnetic field of a plane electromagnetic wave is given by $$B=(400 \propto \mathrm{T})\sin \left[\left(4.0 \times 10^{15} \mathrm{~s}^{-1}\right)\left(t-\frac{x}{c}\right)\right]$$. Average energy density corresponding to the electric field is

AP EAPCET 2021 - 19th August Evening Shift
23

In an amplitude modulated signal, the maximum amplitude is $$15 \mathrm{~V}$$ and minimum amplitude is $$5 \mathrm{~V}$$. The amplitude of modulating wave will be

AP EAPCET 2021 - 19th August Evening Shift