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Question
In the figure given alongside, a narrow beam of white light is shown to pass through a triangular glass prism. After passing through the prism, it produces a spectrum YX on the screen.
State the colour seen (i) at X, and (ii) at Y.
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Solution
(i)The colour seen at X is violet (as it is the maximum deviated).
(ii) The colour seen at Y is red (as it is the least deviated).
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