JEE Main 2023PhysicsRay OpticsMediumMCQ

JEE Main 2023Ray Optics Question with Solution

JEE Main 2023 (06 Apr Shift 2)

Question

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R

Assertion A: The phase difference of two light waves change if they travel through different media having same thickness, but different indices of  refraction.

Reason R: The wavelengths of waves are different in different media.

In the light of the above statements, choose the most appropriate answer from the options given below

Choose an option

Show full solutionCorrect option: D
Correct answer
DBoth A and R are correct and R is the correct explanation of A

Step-by-step explanation

When light travels through a medium, its velocity depends on the density of the medium.

The formula to calculate the speed of light can be written as

v=νλ   ...(1)

From equation (1), it can be concluded that higher the speed, higher is the wavelength. Hence, the wavelength of light depends on the refractive index of the medium.

Because of changed wavelength the phase difference changes while the two waves travel the same distance.

Thus, both A and R are correct and R is the correct explanation of A.

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About this question

This is a previous-year question from JEE Main 2023, 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.