What is the phenomenon responsible for the formation of a rainbow in the sky after rainfall?

💡 Solution & Explanation

Rainbow formation is an optical phenomenon caused by the combined effects of dispersion, refraction, and total internal reflection of sunlight passing through spherical water droplets suspended in the atmosphere. Sunlight refracts upon entering a droplet, disperses into its component spectrum, reflects off the inner back surface, and refracts again as it exits toward the observer. Scattering accounts for the blue color of the clear daytime sky rather than rainbow spectra.