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प्रश्न
What are ultrasonic waves ? Name two animals which can produce ultrasonic waves.
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उत्तर
Ultrasonic sound waves have frequencies higher than 20 kHz. It is inaudible as its frequency lies above the human audible range of frequencies (20 Hz–20 kHz). These sounds are produced by objects vibrating very rapidly. Bats and dolphins can produce these sounds.
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संबंधित प्रश्न
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