FORMATION OF RAINBOW
Seeing the rainbow An observer standing in the right place will see the dispersed sunlight reflected back towards them. Light scattered by many drops reaching the observers eye will appear as a colourful rainbow. Different colours exit the droplets at angles varying by around two degrees from red to violet. The red light seen by an observer comes from drops slightly higher in the atmosphere than the drops that scatter violet light towards the observer. The colours seen are not a pure spectrum, there is some mixing and blurring of the colours. The human eye can pick out many hues but it is still common to think of a rainbow as having seven colours, red , orange, yellow , green, blue, indigo and violet (VIBGYOR).