Angular fringe width, θ=dλ,θ2θ1=d1d2
0.210.20=2d2⇒d2=0.210.20×2=1.9mm
In Young's double slit experiment the separation d between the slits is 2 mm, the wavelength λ of the light used is 5896 Å and distance D between the…
NEET UG 2018 — Physics Optics
2018mcqmedium
In Young's double slit experiment the separation d between the slits is 2mm, the wavelength λ of the light used is 5896Å and distance D between the screen and slits is 100cm. It is found that the angular width of the fringes is 0.20∘. To increase the fringe angular width to 0.21o (with same λandD) the separation between the slits needs to be changed to
Official previous-year question
Held on 30 Apr 2018 · Verified 9 Jul 2026.
Options
- A
2.1mm
- B
1.9mm
- C
1.8mm
- D
1.7mm
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