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Question
The speed of light in air is 3 × 108 ms-1. Calculate the speed of light in water. The refractive index of water is 4/3.
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Solution
The refractive index of water `="Speed of light in air"/"Speed of light in water"`
∴ Speed of light in water `="Speed of light in air"/"Refractive index of water"`
= `(3xx10^8)/(4//3)`
= 2.25 × 108 ms−1.
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