A rainbow is regarded as one of the most spectacular light shows observed on the earth. A rainbow is a multicoloured arc made due to the striking of light on water droplets. Rainbow is produced after the rain, by reflection, refraction and light dispersion process in droplets of water. All such events develop a light spectrum in the sky are called rainbow.
The necessary conditions for the formation of the rainbow:
- Presence of raindrops.
Sun should be at your back to observe the rainbow.
Because of the dispersion, white light separates into different colors when entering the raindrop, causing less refraction of red light than blue light.
Formation of the rainbow:
Light rays, reach the drop near its top level. At first, there is refraction, then the dispersion of white light into colours of a different wavelength.
The violet is the most deviated and red is the least deviated colour.
Reaching the opposite side of the drop, each colour is refracted back into the drop due to the complete internal reflection that hits the drop surface.
Every colour is refracted to the air again.
- We experience the rainbow when we observe in between 42-40 degrees.