The speed of light in a medium is inversely proportional to the refractive index of the material. Therefore,
μBμA=vAvB=21
Let the thickness is d
⇒t2−t1=vBd−vAd=5×10−10s
As vA=2vB⇒d=5×10−10×2vB
⇒d=5×10−10×vAm.
Time taken by light to travel in two different materials A and B of refractive indices μ _A and μ _B of same thickness is t_1 and t_2 respectively.…
JEE Main 2022 — Physics Optics
2022mcqeasy
Time taken by light to travel in two different materials A and B of refractive indices μA and μB of same thickness is t1 and t2 respectively. If t2−t1=5×10−10s and the ratio of μA to μB is 1:2. Then the thickness of material, in meter is: (Given vA and vB are velocities of light in A and B materials respectively).
Official previous-year question
Held on 25 Jul 2022 · Verified 6 Jul 2026.
Options
- A
5×10−10vAm
- B
5×10−10m
- C
1.5×1010m
- D
5×10−10vBm
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