In diffraction, dsin30∘=λ, λ=2d
Young’s fringe width [ d′- the separation between two slits]
β=d′λ×D⇒10−2=2d×d′50×10−2
⇒10−2=2×d′10−6×50×10−2⇒d′=25μm.
The angular width of the central maximum in a single slit diffraction pattern is 60∘ . The width of the slit is 1μm. The slit is illuminated by monochromatic plane waves. If another slit of the same width is made near it, Young's fringes can be observed on a screen placed at a distance 50cm from the slits. If the observed fringe width is 1cm, what is slit separation distance? (i.e., the distance between the centres of each slit.)
Held on 8 Apr 2018 · Verified 6 Jul 2026.
100μm
25μm
50μm
75μm
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