Solved UPSC CDS/OTA Question
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Q · Waves and SoundModerate · 45s
Which of the following is true for ultrasonic waves? Their frequency is greater than 20 kHz. Bats use ultrasonic waves for echolocation. Humans can hear ultrasonic waves easily. 79
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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Humans cannot hear ultrasonic waves; normal range is 20 Hz–20 kHz.
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Final Answer: Option A — 1 and 2 only
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