Solved UPSC CDS/OTA Question
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Q · Optics-Refraction of LightMedium · 45s
Under which of the following conditions does Total Internal Reflection (TIR) occur?
TopicOptics-Refraction of Light
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Total Internal Reflection occurs only when light travels from a denser to a rarer medium, and the angle of incidence is greater than the critical angle. It cannot happen when going from rarer to denser.
Final Answer: Option B - When light travels from a denser to a rarer medium, and the angle of incidence exceeds the critical angle.