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When a beam of white light is passed thr...

When a beam of white light is passed through a triangular glass prism, it gets dispersed into its component colours. Why do we get these colours ? In the given figure, the colours X and Y represent the extreme components of the spectrum. Identify X and Y.

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(1) Different colours of light while passing through a prism bend through different angles with respect to the incident ray, as they travel with different speeds, this leads to dispersion of light.
(2)X-violet, Y-red
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