Sound is a wave, a type of lengthwise, which relies on intermediaries in motion so that the properties of sound waves is identical in all respects. As usual, the ear can hear sounds in the frequency range of 20 Hz to 20,0 Hz sound waves with frequencies higher than 20000 Hz. Supersonic waves or also called ultrasonic (ultrasonic) sound frequencies lower than 20 Hz sound waves, called value or an ultrasonic (Infrasonic Wave).
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