Answer the following question.
 
Why do we see a rainbow in the sky only after rainfall?
 
 of sunlight by tiny water droplets present in the atmosphere lead to the formation of rainbow.
 
A rainbow is continually set in a direction  to that of the Sun. The water droplets behave like small prisms. They get  and  the incident sunlight, then internally it gets , and finally, get refracted again when it comes out of the raindrop.