Refractive index n = c/v = (3 × 10⁸)/(2 × 10⁸) = 1.5
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JEE Main 2020 — Physics Optics
easy
mcq
2020
Official previous-year question
Verified 30 May 2026.
Question
The refractive index of a medium where speed of light is 2 × 10⁸ m/s is (c = 3 × 10⁸ m/s):
Options
- A1.2
- B1.5
- C1.8
- D2.0
Solution
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