In air distance of 5th dark fringe is y1
y1=y5thdark =(2×5−1)2dλD=2d9λD
Also, the distance of 8th bright fringe in the medium is y2=y8thBright=8μdλD
y1=y2 (according to question)
29dλD=8μdλD
μ=916=1.78
Young's double slit experiment is first performed in air and then in a medium other than air. It is found that 8^th bright fringe in the medium lies…
NEET UG 2017 — Physics Optics
2017mcqhard
Young's double slit experiment is first performed in air and then in a medium other than air. It is found that 8th bright fringe in the medium lies where 5th dark fringe lies in air. The refractive index of the medium is nearly
Official previous-year question
Held on 30 Apr 2017 · Verified 9 Jul 2026.
Options
- A
1.25
- B
1.59
- C
1.69
- D
1.78
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