When a beam of light is passed through a glass prism,it is split up into its component colours when these colours are allowed to fall on an inverted glass prism,it recombines to produce white light.
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Newton firstly took one prism and passed light into it then he saw white light getting split into seven colors then after he took another and kept it in inverted position then he saw that when seven colours are passed through it , it again forms white light.
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