A narrow beam PQ of white light is passing through a glass prism ABC as shown in the diagram

A narrow beam PQ of white light is passing through a glass prism ABC as shown in the diagram.

Trace it on your answer sheet and show the path of the emergent beam as observed on the screen DE.
(i) Write the name and cause of the phenomenon observed.
(ii)Based on this observation, state the conclusion which can be drawn about the constituents of white light.

The diagram is as shown :

(i) The phenomenon is called dispersion of light. It is because of the reason that different wavelengths of light travel with different speed in the glass prism.
(ii) In a rainbow.
(iii) White light consists of seven different wavelengths viz. violet, indigo, blue, green, yellow, orange and red.