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Question
Which of the following is not involved in formation of a rainbow?
Options
refraction
angular dispersion
angular deviation
total internal reflection
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Solution
Angular deviation
Explanation:
A rainbow is created when raindrops that are suspended in the air scatter sunlight. We perceive a rainbow because of the way light refracts when it enters a raindrop, total internal reflection from the rear of the droplet surface, and further refracted out in the atmosphere. So all the given processes, i.e., total internal reflection, refraction, and dispersion, take place in the rainbow formation. Angular deviation of light doesn't occur in the formation of a rainbow.
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