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Question
The speed of light in glass is 2 × 105 km/s. What is the refractive index of glass?
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Solution
Given:
Speed of light in glass = 2 x 105 km/s = 2 x 108 m/s
Refractive index of glass is
`mu_"glass" = (3 xx 10^8)/(2xx10^8) = 1.5`
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