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Question
Write the approximate values of speed of light in (i) air and (ii) glass. Use these values to calculate the refractive index of glass with respect to air.
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Solution
(i) Speed of light in air = 3 × 108 ms-1
(ii) Speed of light in glass = 2 × 108 ms-1
Refractive index of glass with respect to air
= `"Speed of light in air"/"Speed of light in glass"`
= `(3xx10^8)/(2xx10^8)`
= `3/2`
= 1.5
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