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Question
Numerical problems.
The speed of light in water is 2.25 × 108 ms–1. If the speed of light in vacuum is 3 × 108 ms–1, calculate the refractive index of water.
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Solution
Given: Speed of light in water (υ) = 2.25 × 108ms– 1
Speed of light in vacuum (c) = 3 × 108ms– 1
Solution:
μ = `"c"/"υ"` ⇒ μ =`(3×10^8"ms"^(−1))/(2.25×10^8"ms"^(−1))`
∴ μ = 1.33
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