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Question
The refractive index of air with respect to glass is defined: as gµa = sin i/sin r
If r = 90°, what is the corresponding angle i called?
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Solution
Given: gμa = `Sin "i"/Sin "r"`
If r = 90°
then aμg = `(Sin90°)/Sin "i"=1/Sin "i"`
The corresponding angle i is called the critical angle for the given pair of media.
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