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The minimum volume that the human ear can hear is 0dB, that is, there is "sound" from above 0dB

When an object is excited, it will generate vibration, and the vibration is back and forth periodically, so it will push the air around the sounding body, allowing the air to conduct dense and dense conduction. What we call "sound waves" is that the sounding body agitates the air in a specific complex vibration period (frequency), and transmits the complex vibration period of the sounding body to the ear, enters the external auditory meatus, the eardrum, the middle ear, the three ear snare drums, and the inner ear , Let our brain perceive sound, this is called the sound wave.

The minimum volume that the human ear can hear is 0dB, that is, there is "sound" from above 0dB