JEE Main 2009 — Wave Optics Question with Solution
From: AIEEE 2009
Question
A mixture of light, consisting of wavelength and an unknown wavelength, illuminates Young's double slit and gives rise to two overlapping interference patterns on the screen. The central maximum of both lights coincide. Further, it is observed that the third bright fringe of known light coincides with the th bright fringe of the unknown light. From this data, the wavelength of the unknown light is :
Choose an option
Show full solutionCorrect option: B
Correct answer
B
Step-by-step explanation
Third bright fringe of known light coincides with the 4th bright fringe of the unknown light.
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This is a previous-year question from JEE Main 2009, 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.