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Question
The refractive index of glass for light going from air to glass is The refractive index for light going from glass to air will be:
(a) `1/3`
(b) `4/5`
(c) `4/6`
(d) `5/2`
Solution
4/6
Explanation:
Refractive index of material 2 with respect to material 1 is given by:
1n2 =`"speed of light in medium 1"/"speed of light in medium 2"`
By the same argument, refractive index of medium 1 with respect to medium 2 is given by:
2n1 = `"speed of light in medium 2"/"speed of lighht in medium 1"`=1/1n2
1n2 is `3/2` therefore, 2n1 will be 1/ `3/2`
Therefore, refractive index of light going from glass to air will be 4/6.
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OR
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