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Question
If the speed of light in vacuum is 3 × 108 ms−1, find the speed of light in a medium of absolute refractive index 1.5.
Solution
Given:-
Speed of light in vacuum = 3 × 108 ms−1
Refractive index of the medium:
`n_m="Speed of light in vacuum"/"Speed of light in medium"`
`rArr1.5=(3xx10^8)/v`
`rArrv=(3xx10^8)/1.5=2xx10^8" m/s"`
Hence, the speed of light in the medium of refractive index 1.5 is 2 × 108 m/s.
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