JEE Main 2023 · PhysicsMultiple choiceSingle correctEasyRecall

JEE Main 8 April 2023, Shift 1, Physics Q45

Question 45 of 90 in this shift, Physics question 15 of 30, Section A.

In a reflecting telescope, a secondary mirror is used to:

(1)remove spherical aberration
(2)move the eyepiece outside the telescopic tubeOfficial answer
(3)make chromatic aberration zero
(4)reduce the problem of mechanical support

Official answer

Option 2

NTA final key.

Chapter: Ray Optics and Optical Instruments
Topic: Optical Instruments
Idea tested: Reflecting Telescopes

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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 108 of the 174 JEE Main shifts held from 2017 to 2026.