JEE Main 2023 · PhysicsMultiple choiceSingle correctEasyApplication

JEE Main 11 April 2023, Shift 1, Physics Q35

Question 35 of 90 in this shift, Physics question 5 of 30, Section A.

The 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 light in the denser medium is:

(1) $2.12 \times 10^8$ m/sOfficial answer
(2) $3.12 \times 10^7$ m/s
(3) $5 \times 10^7$ m/s
(4) $\sqrt{2} \times 10^8$ m/s

Official answer

Option 1

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
25 Jun 2022, Shift 1 · Q44A light wave travelling linearly in a medium of dielectric constant 4, incidents on the horizontal interface separating medium with air.…MediumSingle 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.