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Question
In what condition a prism is said to be in the position of minimum deviation? What is the direction of the refracted ray inside the prism in this condition?
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Solution
A prism is said to be in the position of minimum deviation when the angle of incidence of the light ray at the first prism surface is equal to the angle of emergence at the second surface of the prism.
In this condition, the refracted ray inside the prism is parallel to the base of the prism (if the prism is equilateral).
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