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Question
Explain how the formation of a rainbow occurs.
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Solution
- The beautiful phenomenon of the rainbow is a combination of different phenomena – dispersion, refraction, and reflection of light.
- The rainbow appears in the sky after a rain shower.
- The water droplets act as small prisms.
- When sunlight enters the water droplets present in the atmosphere, they refract and disperse the incident sunlight.
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Then they reflect it internally inside the droplet and finally again refract it.
- As a collective effect of all these phenomena, the seven coloured rainbows are observed.
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