Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Waves and SoundModerate · 45s
Which of the following frequencies is infrasonic? 244
TopicWaves and Sound
Question Typemultiple choice
DifficultyModerate
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
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Infrasonic: below 20 Hz; ultrasonic: above 20 kHz.
252
Final Answer: Option A — 10 Hz
247