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Question
A ray of monochromatic light is incident from air into a glass slab. Draw a labelled ray diagram indicating the change in its path till it emerges out of the slab. In the diagram, mark the angle of incidence (i) and the angle of refraction (r) at the first interface. How is the refractive index of glass related to the angles i and r?
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Solution
The labelled ray diagram is shown in the figure.

Refractive index of glass = `Sin "i"/Sin "r"`
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