JEE Main 2021PhysicsRay OpticsHardNumerical

JEE Main 2021Ray Optics Question with Solution

JEE Main 2021 (27 Jul Shift 1)

Question

A prism of refractive index n1 and another prism of refractive index n2 are stuck together (as shown in the figure). n1 and n2 depend on λ, the wavelength of light, according to the relation n1=1.2+10.8×10-14λ2 and n2=1.45+1.8×10-14λ2 

The wavelength for which rays incident at any angle on the interface BC pass through without bending at that interface will be ____ nm.

Enter your answer

Show full solutionCorrect answer: 600
Correct answer
600

Step-by-step explanation

For no bending, n1=n2
1.2+10.8×10-14λ2=1.45+1.8×10-4λ2
On solving,
9×10-14=25λ2
λ=6×10-7
λ=600 nm

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About this question

This is a previous-year question from JEE Main 2021, 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.