JEE Main 2020PhysicsRay OpticsHardMCQ

JEE Main 2020 — Ray Optics Question with Solution

JEE Main 2020 (06 Sep Shift 2)

Question

A double convex lens has power P and same radii of curvature r of both the surfaces. The radius of curvature of a surface of a plano-convex lens made of the same material with power 1.5 P is :

Choose an option

Show full solutionCorrect option: D
Correct answer
DR3

Step-by-step explanation

1P=(n-1)1R-1-R

1P=(n-1)2R             .........1

11.5P=(n-1)1R-1∞      .......ii

23P=n-1R 

From i and ii

32=R'2R

⇒ R'=R3

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About this question

This is a previous-year question from JEE Main 2020, 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.