Sound wave is one of the categories belonging to sound. It belongs to mechanical wave. Sound wave is a kind of longitudinal wave that can be felt by human ear. Its frequency range is 16Hz-20KHz.

When the frequency of the sound wave is lower than 16Hz, it is called the subsonic wave, and when it is higher than 20KHz, it is called the ultrasonic wave.

Ultrasound has the following characteristics:

  • Ultrasound can be effectively transmitted in media such as gases, liquids, solids, and solid solutions.
  • Ultrasonic waves can transmit very strong energy.
  • Ultrasound produce reflections, interference, superposition, and resonance.
  • When ultrasonic waves spread in a liquid medium, strong impact and cavitation can occur at the interface.