JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyApplication

JEE Main 3 August 2021, Shift 2, Physics Q16

Question 16 of 90 in this shift, Physics question 16 of 30, Section A.

If a man having the least distance of distinct vision of 50 cm, what should be the focal length of the spectacles for the man ?

(1) $-50$ cm
(2) $+50$ cmOfficial answer
(3) $+100$ cm
(4) $+25$ cm

Official answer

Option 2

NTA final key.

Chapter: Ray Optics and Optical Instruments
Topic: Optical Instruments
Idea tested: Hypermetropia Correction

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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.