JEE Main 2026 — Wave Optics Question with Solution
JEE Main 2026 (04 April Shift 2)
Question
In a double slit experiment, when one of the slits is covered by a transparent mica sheet of refractive index , the central fringe shifts to the position of bright fringe, obtained with both slits uncovered. If the light source wavelength is nm, the thickness of mica sheet is m. The value of is ______.
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Show full solutionCorrect answer: 5625
Correct answer
5625
Step-by-step explanation
The shift in the central fringe due to the introduction of a transparent sheet of thickness and refractive index is given by .
The position of the bright fringe is .
Equating the two, we get:
Substituting the given values:
m
Comparing with m, we get .
Answer:
The position of the bright fringe is .
Equating the two, we get:
Substituting the given values:
m
Comparing with m, we get .
Answer:
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This is a previous-year question from JEE Main 2026, 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.