1）What's ultrasonic wave
sound waves are divided into three types, infrasonic waves, sound waves, and ultrasonic waves. The frequencies of infrasonic waves are below 20hz, the frequencies of sound waves are in the range of 20hz~20khz, the frequencies of ultrasonic waves are above 20khz. Infrasonic waves and ultrasonic waves are inaudible to the human ear. Ultrasonic waves have many features like high frequency, short wavelength, good directivity and penetrability in propagation. That's why they are used for design and production of ultrasonic cleaning tank.
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