JEE Main 2025 Physics question
Assertion (A) : If Young's double slit experiment is performed in an optically denser medium than air, then the consecutive fringes come closer. Reason (R) : The speed of light reduces in an optically denser medium than air while its frequency does not change. In the light of the above statements, choose the most appropriate answer from the options given below :
Answer: (1)
Solution
In denser medium wavelength decreases (λmed = λvac/μ), so fringe width β=λD/d decreases, fringes come closer. R correctly explains A.