JEE Main 2024PhysicsWave OpticsHardMCQ

JEE Main 2024 — Wave Optics Question with Solution

JEE Main 2024 (30 Jan Shift 1)

Question

The diffraction pattern of a light of wavelength 400 nm diffracting from a slit of width 0.2 mm is focused on the focal plane of a convex lens of focal length 100 cm. The width of the 1st  secondary maxima will be :

Choose an option

Show full solutionCorrect option: A
Correct answer
A2 mm

Step-by-step explanation

Width of 1st secondary maxima =λa·D

Here

a=0.2×10-3 m

λ=400×10-9 m

D=100×10-2=1 m

Therefore, width of 1st secondary maxima

=400×10-90.2×10-3×1

=2×10-3 m=2 mm

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About this question

This is a previous-year question from JEE Main 2024, covering the Wave 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.