A rainbow is an optical phenomenon produced by illuminated droplets of water. Rainbows are caused by reflection, refraction and dispersion of light in individual droplets and results in the appearance of an arc of spectral colours.
- Rainbows can be produced by meteorological phenomena, waterfalls, lawn sprinklers and other things that create water droplets.
- A rainbow is formed from millions of individual raindrops each of which reflects and refracts a tiny coloured image of the sun towards the observer.
- It is the dispersion of light as refraction takes place that produces the rainbow colours seen by an observer.
- If the sun is behind an observer then the rainbow will appear in front of them.