JEE Main 2026 (Online) 28th January Morning Shift | Electromagnetic Waves Question 16 | Physics

1

JEE Main 2026 (Online) 28th January Morning Shift

MCQ (Single Correct Answer)

+4

-1

The electric field of an electromagnetic wave travelling through a medium is given by $\vec{E}(x, t)=25 \sin \left(2.0 \times 10^{15} t-10^7 x\right) \hat{n}$ then the refractive index of the medium is $\_\_\_\_$ .

(All given measurement are in SI units)

A

2

B

1.2

C

1.5

D

1.7

2

JEE Main 2026 (Online) 24th January Morning Shift

MCQ (Single Correct Answer)

+4

-1

\text { Match the LIST-I with LIST-II }

List-I		List-II
A.	Radio-wave	I.	is produced by Magnetron valve
B.	Micro-wave	II.	due to change in the vibrational modes of atoms
C.	Infrared-wave	III.	due to inner shell electrons moving from higher energy level to lower energy level
D.	X-ray	IV.	due to rapid acceleration of electrons

Choose the correct answer from the options given below:

A

A-IV, B-II, C-I, D-III

B

A-IV, B-III, C-I, D-II

C

A-IV, B-I, C-II, D-III

D

A-II, B-IV, C-III, D-I

3

JEE Main 2026 (Online) 23rd January Evening Shift

MCQ (Single Correct Answer)

+4

-1

The ratio of speeds of electromagnetic waves in vacuum and a medium, having dielectric constant $k=3$ and permeability of $\mu=2 \mu_0$, is ( $\mu_0=$ permeability of vacuum)

A

$6: 1$

B

$3: 2$

C

$\sqrt{6}: 1$

D

$36: 1$

4

JEE Main 2026 (Online) 23rd January Morning Shift

MCQ (Single Correct Answer)

+4

-1

$$ \text { Match List - I with List - II. } $$

List - I Relation		List - II Law
A.	$$ \oint \vec{E} \cdot \overrightarrow{d l}=-\frac{d}{d t} \oint \vec{B} \cdot \overrightarrow{d a} $$	I.	Ampere's circuital law
B.	$$ \oint \vec{B} \cdot \overrightarrow{d l}=\mu_0\left(I+\epsilon_0 \frac{d \phi_E}{d t}\right) $$	II.	Faraday's laws of electromagnetic induction
C.	$$ \oint \vec{E} \cdot \overrightarrow{d a}=\frac{1}{\epsilon_0} \int_{\mathrm{v}} \rho \mathrm{dv} $$	III.	Ampere - Maxwell law
D.	$$ \oint \vec{B} \cdot \overrightarrow{d l}=\mu_0 I $$	IV.	Gauss's law of electrostatics

Choose the correct answer from the options given below :

A

A-I, B-IV, C-III, D-II

B

A-II, B-III, C-IV, D-I

C

A-IV, B-I, C-II, D-III

D

A-II, B-III, C-I, D-IV

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