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Question
When a beam of white light is passed through a prism, it splits to form lights of seven colours. Is it possible to recombine the lights of seven colours to obtain the white light again? Explain your answer.
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Solution
When a beam of white light is passed through a prism, it splits to form lights of seven colours. It is possible to recombine the lights of seven colours to obtain white light again.
Recombination of colours to form white light again is possible if a second glass prism is placed upside down behind the first prism. A patch of white light is obtained on a screen placed behind the second prism because the refraction produced by the second prism is equal and opposite to the refraction produced by the first prism.
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RELATED QUESTIONS
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Choose the correct answer from the options given below:
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