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Question
The velocity of light in a medium is 1.5 x 108 m/s. What is the refractive index of the medium with respect to air, if the velocity in air is 3 x 108 m/s?
Solution
Given that
`v_1=3xx10^8`
`v_2=1.5xx10^8`
We know that, the refractive index with respect to air is
`n=v_1/v_2`
`therefore n=(3xx10^8)/(1.5xx10^8)`
Thus, the refractive index of the medium with respect to air is 2.
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