A rainbow is a beautiful natural phenomenon that occurs when sunlight interacts with raindrops in the atmosphere. The process behind a rainbow involves three main actions reflection, refraction, and dispersion. As sunlight enters a raindrop, it bends (refracts) and then reflects off the inside surface of the drop. When it exits the droplet, the light bends again and spreads out into its different color components red, orange, yellow, green, blue, indigo, and violet. This separation of light into colors is what we see as a rainbow.
Why Do Rainbows Appear in an Arc
The arc shape of a rainbow is due to the specific angle at which light is refracted and reflected inside water droplets. Most rainbows are seen when the sun is low in the sky, typically in the early morning or late afternoon. The observer must be standing with their back to the sun, and the raindrops must be in front of them. Light reflecting at about 42 degrees from the direction opposite the sun creates the circular arc. However, because the ground blocks the bottom half, we usually only see a semi-circle. From high altitudes, such as in an airplane, a full circle rainbow can sometimes be seen. Shutdown123