JEE Main 2022 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 25 June 2022, Shift 1, Physics Q44

Question 44 of 90 in this shift, Physics question 14 of 30, Section A.

A light wave travelling linearly in a medium of dielectric constant 4, incidents on the horizontal interface separating medium with air. The angle of incidence for which the total intensity of incident wave will be reflected back into the same medium will be : (Given : relative permeability of medium

\mu_r=1

)

(1) $10^\circ$
(2) $20^\circ$
(3) $30^\circ$
(4) $60^\circ$ Official answer

Official answer

Option 4

NTA final key.

Chapter: Ray Optics and Optical Instruments
Topic: Refraction and Snell's Law
Idea tested: Total Internal Reflection

Same idea in other shifts

Asked 9× in all

7 Apr 2025, Shift 2 · Q42A transparent block A having refractive index $\mu=1.25$ is surrounded by another medium of refractive index $\mu=1.0$ as shown in figure.…MediumSingle correctHas a figure
8 Apr 2024, Shift 1 · Q43Critical angle of incidence for a pair of optical media is $45^\circ$ . The refractive indices of first and second media are in the ratio:EasySingle correct
11 Apr 2023, Shift 1 · Q35The critical angle for a denser-rarer interface is $45^\circ$ . The speed of light in rarer medium is $3 \times 10^8$ m/s. The speed of…EasySingle correct
22 Jul 2021, Shift 2 · Q3A ray of light passes from a denser medium to a rarer medium at an angle of incidence $i$ . The reflected and refracted rays make an angle…MediumSingle correctHas a figure
25 Jul 2021, Shift 1 · Q9A ray of laser of a wavelength 630 nm is incident at an angle of $30^\circ$ at the diamond-air interface. It is going from diamond to air.…EasySingle correct
25 Jul 2021, Shift 2 · Q16A ray of light entering from air into a denser medium of refractive index $\frac{4}{3}$ , as shown in figure. The light ray suffers total…MediumDiagram basedHas a figure
8 Jan 2020, Shift 1 · Q15The critical angle of a medium for a specific wavelength, if the medium has relative permittivity 3 and relative permeability…MediumSingle correct
9 Jan 2020, Shift 2 · Q17There is a small source of light at some depth below the surface of water (refractive index $= \frac{4}{3}$ ) in a tank of large cross…HardSingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.