In Young's double slit experiment, the distance between the two coherent sources is ' d ' and the distance between the source and screen is ' D '. When the wavelength (λ) of light source used is d²/3D, then n th dark fringe is observed on the screen, exactly in front of one of the slits. The value of ' n ' is (a) 1 (b) 2 (c) 3 (d) 4

Answer: (b). For the n th dark fringe in front of a slit: λ = (d²)/((2n-1)D). d²/3D = (d²)/((2n-1)D) ⇒ 2n - 1 = 3 ⇒ n = 2 So the answer is (b) 2.

In Young's double slit experiment, the distance between the two… | MHT CET 2024 (10 May, Shift 2)

Q36MHT CET 2024 · 10 MAY · SHIFT 2Medium

YDSE: Film, Medium & Two Wavelengths

In Young's double slit experiment, the distance between the two coherent sources is ' d ' and the distance between the source and screen is ' D '. When the wavelength $(\lambda)$ of light source used is $\frac{d^2}{3D}$ , then $n$ th dark fringe is observed on the screen, exactly in front of one of the slits. The value of ' $n$ ' is

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Answer: (b)

For the $n$ th dark fringe in front of a slit: $\lambda = \dfrac{d^2}{(2n-1)D}$ .
$\dfrac{d^2}{3D} = \dfrac{d^2}{(2n-1)D} \Rightarrow 2n - 1 = 3 \Rightarrow n = 2$
So the answer is (b) 2.

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YDSE: Film, Medium & Two Wavelengths question from MHT CET 2024 (10 May, Shift 2)

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