Question

the formation of rainbow

Answer 1

A rainbow is an optical and meteorological phenomenon that is caused by both reflection and refraction of light in water droplets resulting in a spectrum of light appearing in the sky. It takes the form of a multicoloured arc. Rainbows caused by sunlight always appear in the section of sky directly opposite the sun.

Answer 2

Rainbow is formed when sunlight passes through the water droplets during rain,and these light split up into seven colors forming a band like structure.
In this case water acts as prism and reflects seven colors ( VIBGYOR)