Question

What do you mean by infrasonic sound​

Answer 1

Infrasonics, vibrational or stress waves in elastic media, having a frequency below those of sound waves that can be detected by the human ear—i.e., below 20 hertz. The range of frequencies extends down to geologic vibrations that complete one cycle in 100 seconds or longer.

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Answer 2

• sounds with a frequency below 20hz (hertz) are known as infrasonic sounds.
• they are also known as inaudible sounds, as they cannot be heard by human ears.

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