When white light is reflected from the surface of a Compact Disc … - Vidyadip

Question

When white light is reflected from the surface of a Compact Disc (CD), many colours are seen. When we blow soap bubbles, they appear colourful. The disc painted with seven colours of the spectrum is called Newton's disc.

David spins a multicoloured wheel rapidly.
(i) What colour will the rapidly spinning wheel appear to be?
(ii) What acts like a prism in the formation of a rainbow in nature?
(iii) What happen when we pass a red laser light through the prism?

✓

Answer

(i) It will appear to white as all colours mix due to rotation and give white light.
(ii) Raindrops act like prisms when sunlight passes through them to form a rainbow.
(iii) When a red laser light passes through a prism, it stays together and appears as one colour, i.e. red.

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