How Are Rainbows Formed?

Rainbows are arc shaped and can be seen in that part of the sky opposite the sun. A rainbow is made up of 7 colors - violet, indigo, blue, green, yellow, orange and red but most of the time these colors are blended together and as such we normally see only 4 or 5 of them clearly. Rainbows are caused by refraction (bending) and reflection of the rays of the sun as it falls on the raindrops. The tiny drop of water acts as a prism and as the rays of the sun pass through these drops of rain they are refracted and are separated into different colors and as the rays of the sun strikes the inner surface of the raindrops, they are further refracted and this causes the rainbow. At times when the rainfall is heavy, the rainbow may be spread in such a way that its ends seem to meet the earth at the horizon.