Wavelength of light used is inversely proportional to number of fringes observed.
Hence, we can write:
n1λ1=n2λ2⇒n2=λ2n1λ1=(400×10−9)8×(600×10−9)=12
In a Young's double slit experiment, a student observes 8 fringes in a certain segment of screen when a monochromatic light of 600 nm wavelength is…
NEET UG 2022 — Physics Optics
2022mcqmedium
In a Young's double slit experiment, a student observes 8 fringes in a certain segment of screen when a monochromatic light of 600nm wavelength is used. If the wavelength of light is changed to 400nm, then the number of fringes he would observe in the same region of the screen is:
Official previous-year question
Held on 30 Apr 2022 · Verified 9 Jul 2026.
Options
- A
8
- B
9
- C
12
- D
6
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