JEE Main 2021PhysicsRay OpticsEasyMCQ

JEE Main 2021 — Ray Optics Question with Solution

JEE Main 2021 (16 Mar Shift 2)

Question

The refractive index of a converging lens is 1.4. What will be the focal length of this lens if it is placed in a medium of same refractive index ? (Assume the radii of curvature of the faces of lens are R1 and R2 respectively)

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Show full solutionCorrect option: B
Correct answer
BInfinite

Step-by-step explanation

1 F=μLμS-11R1-1R2

If μL=μS⇒1 F=0⇒F=∞

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About this question

This is a previous-year question from JEE Main 2021, covering the Ray Optics chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.