JEE Main 2021 — Wave Optics Question with Solution
From: JEE Main 2021 (Online) 26th August Morning Shift
Question
White light is passed through a double slit and interference is observed on a screen 1.5 m away. The separation between the slits is 0.3 mm. The first violet and red fringes are formed 2.0 mm and 3.5 mm away from the central white fringes. the difference in wavelengths of red and violet light is ................ nm.
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Show full solutionCorrect answer: 300
Correct answer
300
Step-by-step explanation
Position of bright fringe y = n
y1 of red = = 3.5 mm
r = 3.5 103
Similarly, v = 2 103
= 3 107 = 300 nm
y1 of red = = 3.5 mm
r = 3.5 103
Similarly, v = 2 103
= 3 107 = 300 nm
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