Question

1. A ray of white light breaks up into its components while passing through a glass prism. Draw a ray diagram to show the path of rays.
2. Mark the least deviated colour in your diagram.
3. Why do different coloured rays deviate differently in a prism?

Answer 1

1. The splitting of white light into its component colours on passing through a glass prism is shown in the following diagram. 
2. The least deviated colour is red, which is marked in the diagram.
3. Different colours have different wavelengths; therefore, they deviate differently when passing through a glass prism. The amount of deviation depends on the wavelength of the coloured light.