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प्रश्न
What are infrasonic waves ? Name two animals which produce infrasonic waves.
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उत्तर
Infrasonic sound waves have frequencies lesser than 20 Hz. It is inaudible as its frequency lies below the human audible range of frequencies (20 Hz–20 kHz). These sounds are produced by objects vibrating very slowly. Whales and elephants can produce these sounds.
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संबंधित प्रश्न
What is the range of frequencies associated with infrasound?
A person has a hearing range from 20 Hz to 20 kHz. What are the typical wavelengths of sound waves in air corresponding to these two frequencies? Take the speed of sound in air as 344 m s−1.
Fill in the blanks with suitable words.
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(b) Name one device which can produce sound like X.
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(d) Name one device in our homes which can produce sound like Z.
(e) What is the frequency range of sounds like Z ?
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