Why is a rainbow colorful?

Answer 1

It is refraction. The different wavelengths of light split creating pretty colours. it's like when you shine light through a pyramid made of crystal except that minute droplets of water act as a series of prisms.

Answer 2

White light contains all the colours. When you shine it through something - like a crystal, or a drop of water or mist - the light gets refracted (it changes angle and becomes a thicker beam) and splits into the different frequencies. You can then see red, yellow, orange, and so forth.

As the light hits the mist, it gets slowed down and its angle gets changed. It goes in as one beam, and comes out in a y-shape. (Imagine a funnel.) As that y-shape opens out, the light is coming out at different speeds, which display as colour. rays of light are reflected from the back of surfaces of rain drops and refracted again as they exit the rain drop and return to our eyes. REFRACTION is the cause of spliting the sunlight into colours.

Answer 3

So you can see them.