JEE Main 2026 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 6 April 2026, Shift 2, Physics Q42

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

Angle of minimum deviation is equal to the half of the angle of prism in an equilateral prism. The refractive index of the prism is __________.

(1)1.5
(2) $\sqrt{3}$
(3) $\sqrt{2}$ Official answer
(4)1.65

Official answer

Option 3

NTA final key.

Chapter: Ray Optics and Optical Instruments
Topic: Prism Deviation
Idea tested: Prism Refractive Index

Same idea in other shifts

Asked 3× in all

2 Apr 2025, Shift 2 · Q49A ray of light suffers minimum deviation when incident on a prism having angle of the prism equal to $60^\circ$ . The refractive index of…EasyNumerical value
28 Jun 2022, Shift 1 · Q42The refracting angle of a prism is A and refractive index of the material of the prism is cot (A/2). Then the angle of minimum deviation…MediumSingle 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.