JEE Main 2020PhysicsRay OpticsMediumNumerical

JEE Main 2020 — Ray Optics Question with Solution

JEE Main 2020 (05 Sep Shift 1)

Question

A compound microscope consists of an objective lens of focal length 1 cm and an eye piece of focal length 5 cm with a separation of 10 cm. The distance between an object and the objective lens, at which the strain on the eye is minimum is n40cm. The value of n is.......

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Show full solutionCorrect answer: 50
Correct answer
50

Step-by-step explanation

L=10
Ve=∞

ue=fe=5
V0=10-5=5

1v0-1u0=1f0
15-1u0=11
u0=-54cm
54=n40
n=50

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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.