Solved UPSC CDS/OTA Question
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Q · Optics-Refraction of LightMedium · 45s
When does a ray of light passing through a prism undergo minimum deviation?
TopicOptics-Refraction of Light
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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At the position of minimum deviation, the light ray travels symmetrically through the prism, meaning the angle of incidence is equal to the angle of emergence. This is a key condition in prism optics.
Final Answer: Option C - When the angle of incidence equals the angle of emergence.