JEE Main 2026 — Ray Optics Question with Solution
JEE Main 2026 (21 January Shift 1)
Question
A collimated beam of light of diameter 2 mm is propagating along -axis. The beam is required to be expanded in a collimated beam of diameter 14 mm using a system of two convex lenses. If first lens has focal length 40 mm, then the focal length of second lens is mm.
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Show full solutionCorrect answer: 280
Correct answer
280
Step-by-step explanation
For beam expander using two convex lenses:
Magnification
mm
Magnification
mm
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This is a previous-year question from JEE Main 2026, 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.