Solved UPSC CDS/OTA Question
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Q · Modern PhysicsMedium · 45s
Lasers for Distance Measurement Why are lasers used to measure distances, such as to the moon?
TopicModern Physics
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Lasers are highly coherent, focused, and maintain narrow beams over long distances—perfect for precise measurements.
Final Answer: Option A - They are coherent light sources