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Question
Light travels with a velocity 1.5 x 108 m/s in a medium. On entering second medium its velocity becomes 0.75 x 108 m/s. What is the refractive index of the second medium with respect to the first medium?
Solution
Given :
Velocity of light in a first medium = V1 = 1.5 x 108 m/s
Velocity of light in second medium = V2 = 0.75 x 108 m/s
Refractive index of second medium = 2n1 = ?
2n1 =
2n_1
= 2
Hence, the refractive index of second medium with respect to first medium is 2.
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