Blog Log in Get Started Free

Electromagnetic Waves MCQs for NEET — Physics Questions with Answers

Practice free Electromagnetic Waves (Physics) NEET multiple-choice questions online with instant answers and detailed explanations. No login required.

All Physics Chemistry Botany Zoology

Language English हिंदी

Chapter Difficulty Show only questions I answered incorrectly Clear Register free for difficulty & keyword filters

● ● ● ● ●

The S.I unit of displacement current is

Henry

Coulomb

Ampere

Farad

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

Displacement current’s SI unit is ampere.

● ● ● ● ●

The relation between electric field E and magnetic field H in an electromagnetic wave is

E = H

$E = \frac{μ_{0}}{ε_{0}} H$

$E = \sqrt{\frac{μ_{0}}{ε_{0}}} H$

$E = \sqrt{\frac{μ_{0}}{μ_{0}}} H$

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

$E = \sqrt{\frac{μ_{0}}{ε_{0}}} H$

● ● ● ● ●

An electromagnetic wave going through Vaccum is described by

$E = E_{0} \sin (k x - ω t) B = B_{0} \sin (k x - ω t)$

$E_{0} B_{0} = ω k$

$E_{0} ω = B_{0} k$

$E_{0} k = B_{0} ω$

none of these

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

For an electromagnetic wave,

$E_{0} = C B_{0} = \frac{ω}{K} B_{0} K E_{0} = B_{0} ω$

● ● ● ● ●

The ratio of $\frac{E_{0}}{H_{0}}$ for a plane electromagnetic wave has the dimension of

Impedance

Resistance

Both

None

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

$F o r v a c c u m, E_{o} = B_{o} c B_{o} = μ_{o} H_{o} S o, [E_{o}] = \frac{F o r c e}{C h a r g e} [H_{o}] = \frac{C u r r e n t}{L e n g t h} [\frac{E_{o}}{H_{o}}] = \frac{W o r k}{C h a r g e \times C u r r e n t} = \frac{P o t e n t i a l}{C u r r e n t} = R e s i s \tan c e$

● ● ● ● ●

An electromagnetic wave going through a medium is given by $E = E_{0} \sin (k x - ω t) a n d B = B_{0} \sin (k x - ω t)$ then

$E_{0} k = B_{0} ω$

If Electric is in Z direction them magnetic field should be in -y direction

Both 'A' and 'B' are correct

Only A is correct

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

We know,

$E_{0} = v_{w} . B_{0} E_{0} = \frac{ω}{K} B_{0} E_{0} K = B_{0} ω$

As the wave is traveling along -x-direction, the magnetic field should be along +y-direction so that the direction of $\vec{E} \times \vec{B}$ is along the direction of the wave.

● ● ● ● ●

A plane E M wave of frequency 25 MHz travels in free space in the x-direction. At a particular point in space and time $E = 6.3 \hat{j} V / m$ then B at the point is

$2.1 \times 10^{- 8} - \hat{k}$

$2.1 \times 10^{- 8} \hat{k}$

2.1 $\hat{k}$

$2.1 \times 10^{- 8} \hat{i}$

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

$B = \frac{E}{c} = \frac{6.3}{3 \times 10^{8}} = 2.1 \times 10^{- 8} W b \vec{E} \times \vec{B} s h o u l d b e i n + x - d o r e c t i o n a s t h e w a v e i s p r o p a g a t i n g a l o n g + x - d i r e c t i o n . S o, \vec{B} = 2.1 \times 10^{- 8} \hat{k}$

● ● ● ● ●

In an electromagnetic wave, the amplitude of electric field is 1 V/m. The frequency of wave is $5 \times 10^{14} H z$ . The wave is propagating along Z-axis. The average energy density of electric field in joule/ $m^{3}$ , will be

$2.2 \times 10^{- 12}$

4.4 $\times 10^{- 12}$

6.6 $\times 10^{- 12}$

8.8 $\times 10^{- 12}$

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

Average energy density= $\frac{1}{2} \in_{0} {(\frac{E}{\sqrt{2}})}^{2}$

$\frac{1}{2} \times 8.85 \times 10^{- 12} \times {(\frac{1}{\sqrt{2}})}^{2} = 2.21 \times 10^{- 12} J / m^{3}$

● ● ● ● ●

The infra-red spectrum lies between :

radio wave and microwave region

the micro-wave and visible region

the visible and ultraviolet region

the ultraviolet and the X-ray region

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The infra-red spectrum lies between the visible and ultraviolet regions.

● ● ● ● ●

Consider an electric charge oscillating with a frequency of 10 MHz. The radiation emitted will have a wavelength equal to

20 m

30 m

40 m

10 m

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

$λ = \frac{c}{ν} = \frac{3 \times 10^{8}}{10 \times 10^{6}} = 30 m$

● ● ● ● ●

Which of the following electromagnetic waves has minimum frequency?

radio wave

ultrasonic wave

microwave

audible wave

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

Audible waves have the least frequency

Ready to ace NEET?

Free access · No credit card required

Browse All Questions Create Free Account

Frequently Asked Questions

Yes. You can attempt every Electromagnetic Waves question on this page for free without logging in, and check the correct answer with a detailed explanation instantly.

No account is required to attempt questions and view answers. A free account adds bookmarks, personal notes, and progress tracking.

The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.