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Question
Give a reason, why the violet colour of white light deviated most and red colour of white light deviated least.
Solution
The reason is that the speed of violet light in glass is least while that of red light is most. Since. Refractive index of glass = speed of light in air/speed of light in the glass, so the refractive index of glass (the material of prism) is most for violet light and least for the red light. Hence, the violet light has deviated most and red light is deviated least.
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