Rainbow in Water Drops
To make a rainbow
As the light passes through a prism, bending or refraction takes place. The refractive index of prism material is different for different colors. This makes different colors to bend by different angles. This phenomenon is called dispersion.
A sprayer (used by barbers in saloon).
In an open place, with sun behind you, spray water in front. Beautiful rainbow appears in the water droplets. For better results, spray water against a dark background.
Sunlight first refracts while entering the drop, reflects back from the rear surface of the drop and again refracts while leaving the drop.