Solved UPSC CDS/OTA Question
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Q · Optics-Reflection of LightMedium · 45s
Which device works on the principle of reflection of light?
TopicOptics-Reflection of Light
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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A periscope uses plane mirrors placed at 45° to reflect light down the tube, allowing viewers to see over or around obstacles.
Final Answer: Option B - Periscope