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Question
A ray of white light is passed through a glass prism and a spectrum is obtained on a screen.
- Name the seven colours of the spectrum in order.
- Do the colours have the same width in the spectrum?
- Which of the colour of the spectrum of white light deviates (i) the most, (ii) the least?
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Solution
- Violet, Indigo, Blue, Green, Yellow, Orange, and Red.

- No, different colours have different widths in the spectrum.
-
- The violet colour deviates the most.
- The red colour deviates the least.
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