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Question
You are given a disc divided into seven sectors with colours violet, indigo, blue, green, yellow, orange and red in them. What would be its colour when it is rotated rapidly?
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Solution

Newton’s colour disc— It is a circular disc taken by Newton to demonstrate that the recombination of seven colours produces white light. A circular cardboard disc which is divided into seven sectors and they were painted with the seven colours of VIBGYOR. The disc when rotated at a very high speed appears WHITE.
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