Q1. Which of the following events is not related to the phenomenon of refraction of light? Choose the most appropriate option.
A The coin kept at the bottom of a pot containing water appears raised
B Appearance of the Sun before sunrise and after sunset
C Blue colour of the clear sky Correct
D Formation of image by a lens
Explanation
The blue colour of a clear sky is mainly due to scattering of sunlight by molecules in the atmosphere, not refraction. A coin at the bottom of water appears raised because light bends while passing from water to air. The Sun being visible just before sunrise and just after sunset is explained by atmospheric refraction. A lens forms images by refracting light at its curved surfaces. Therefore, among the listed events, the clear sky appearing blue is the one not related to refraction.