Question

Question #8254d

Answer 1

see below

Explanation:

Newton's disc is made with all iride's colors correctly arranged.
The persistence of the image on our retina is of about `0.1` second or, less, for that if the disc is rotated at this speed or faster, we can see the colors all together. Joining all the iride's colors we have the white.

White is absolutely not a colour but a mixture of variety of colours.. When the Newton's disc is rotated only an illusion is formed. So it looks white.
Reference is here.
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