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Question
What do you understand by the deviation produced by a prism? Why is it caused?
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Solution
Prism-produced Deviation is the bending of a light beam away from its intended path. Ray AB would have followed the path if there had been no prism. ABDF, but the prism has forced the light ray to bend twice in the direction of the prism's base, and the emerging beam EK seems to be coming from DEK.
Cause: When light travels from one medium to another, in this example, from air to a glass prism, its speed changes. This change in speed causes the light to deflect and enter the new medium glass at a different angle.
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