JEE Main 2021 — Wave Optics Question with Solution
From: JEE Main 2021 (Online) 27th July Evening Shift
Question
The difference in the number of waves when yellow light propagates through air and vacuum columns of the same thickness is one. The thickness of the air column is ___________ mm. [Refractive index of air = 1.0003, wavelength of yellow light in vacuum = 6000 ]
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Show full solutionCorrect answer: 2
Correct answer
2
Step-by-step explanation
Thickness t = n
So, n vac = (n + 1) air
n = (n + 1)
n =
t = n
= 2 mm
So, n vac = (n + 1) air
n = (n + 1)
n =
t = n
= 2 mm
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This is a previous-year question from JEE Main 2021, 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.