Question

Why is the colour of clear sky blue?

Answer 1

This is because Sunlight is a mixture of several colours which are in the form vibgyor. Now, red is of longer wavelength so it scatter less by the atmosphere small particle but blue colour is of small wavelength therefore it scatter more by the small particle. That's why colour of the sky is blue.

Answer 2

A clear cloudless day-time sky is bluebecause molecules in the air scatterblue light from the sun more than they scatter red light. When we look towards the sun at sunset, we see red and orange colours because the bluelight has been scattered out and away from the line of sight.