Question

How will you prove that light consists of seven colours using Newton's colour disc?

Answer 1

The Newton's disc is a disc with sectors of the seven colours, viz. Violet, Indigo, Blue, Green, Yellow, Orange and Red. To prove that white light is made up of these seven colours, the Newton's disc is rapidly rotated, and the disc appears to be white in colour. This occurs when the rotation of disc occurs at a high angular speed. This proves that the seven colours combine to give white colour.