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Question
Is the speed of light in glass independent of the colour of light? If not, which of the two colours red and violet travels slower in a glass prism?
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Solution
The speed of light in glass is not independent of the colour of light.
The refractive index of a violet component of white light is greater than the refractive index of a red component. Hence, the speed of violet light is less than the speed of red light in glass. Hence, violet light travels slower than red light in a glass prism.
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