Question

we cannot hear sound on vibrating our hands forward and backward


pls​

Answer 1

Answer:

because the frequency of the ear is very low

Answer 2

Answer:

We cannot hear the vibrations that are made by waving our hands in the air because they are too slow. The slowest vibration our human ears can hear is 20 times a second. ... The air molecules vibrate as the sound moves through the air. The eardrum vibrates when the sound wave reaches it.

(Note:human cannot hear infrasonic sound i.e. sound less than 20 hertz.)

Hertz:Hertz (abbreviated: Hz) is the standard unit of measurement used for measuring frequency. Since frequency is measured in cycles per second, one hertz equals one cycle per second. Hertz is used commonly used to measure wave frequencies, such as sound waves, light waves, and radio waves.

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