Angular fringe width is given by θ=Dλ, where, D is the distance between the source and the screen and λ is the wavelength of the light.
We have, θ2θ1=λ2λ1
Then, θ2=450nm0.35∘×57450nm=0.25∘=41 (∵λ2=μλ1)
Thus, value of α=4.
In a Young's double slit experiment, an angular width of the fringe is 0.35∘ on a screen placed at 2m away for particular wavelength of 450nm. The angular width of the fringe, when whole system is immersed in a medium of refractive index 57, is α1. The value of α is _____ .
Held on 28 Jun 2022 · Verified 6 Jul 2026.
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