Question

Deviation of light by prism

Answer 1

This phenomenon is called dispersion. This causes light of different colors to be refracted differently and to leave theprism at different angles, creating an effect similar to a rainbow. This can be used to separate a beam of white lightinto its constituent spectrum of colors.

Answer 2

Light is deflected as it enters a material with refractive index > 1. A ray of light is deflected twice in a prism. The sum of these deflections is the deviation angle. When the entrance and exit angles are equal, the deviationangle of a ray passing through aprism will be a minimum.
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