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Question
How does the deviation produced by a prism depend on the wavelength of incident light?
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Solution
The refractive index of a medium is different for light of different colours. It increases with decrease in wavelength. Thus, the refractive index of the material of prism is maximum for violet and least for red light. Hence, the prism deviates violet light the most and red light the least, i.e., δviolet > δred
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