In air angular fringe width is given by, θ=dλ.
Angular fringe width in water, θ′=μθ=340.2=0.15∘
In a double slit experiment, when light of wavelength 400 nm was used, the angular width of the first minima formed on a screen placed 1 m away was…
NEET UG 2019 — Physics Optics
2019mcqmedium
In a double slit experiment, when light of wavelength 400nm was used, the angular width of the first minima formed on a screen placed 1m away was found to be 0.2∘. What will be the angular width of the first minima, if the entire experimental apparatus is immersed in water? (μwater=34)
Official previous-year question
Held on 30 Apr 2019 · Verified 9 Jul 2026.
Options
- A
0.266∘
- B
0.15∘
- C
0.05∘
- D
0.1∘
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