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Question
Explain the cause of dispersion of white light through a prism.
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Solution
When white light is incident on the first surface of a prism and enters glass, light of different colours due to different speeds in glass, is refracted or deviated through different angles. Thus, the dispersion of white light into its constituent colours takes place at the first surface of the prism. Thus, the cause of dispersion is the change in the speed of light with wavelength or frequency.
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