JEE Main 2025 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 3 April 2025, Shift 2, Physics Q42

Question 42 of 75 in this shift, Physics question 17 of 25, Section A.

A monochromatic light of frequency

5 \times 10^{14}

Hz travelling through air, is incident on a medium of refractive index '2'. Wavelength of the refracted light will be :

(1)300 nmOfficial answer
(2)400 nm
(3)500 nm
(4)600 nm

Official answer

Option 1

NTA final key.

Chapter: Wave Optics
Topic: Refraction and Snell's Law
Idea tested: Invariance of Frequency in Refraction

Same topic in other shifts

All Refraction and Snell's Law questions

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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 42 of the 174 JEE Main shifts held from 2017 to 2026.