A thicker fat pad may attenuate sound. Liquid acoustic windows may be associated with shock wave formation. The velocity of the sound propagation varies with the density of the media. In the compression phase of the wave the density increases and the velocity of the sound wave increases. At high pressure, this can cause the positive components of the wave to bunch up in a steep positive wavefront referred to as a shock wave.
Liquids are conducive to the formation of shock waves.
Sound Parameters Important to Bioeffects 1. Intensity Intensity is the acoustic power transmitted in the direction of the wave propagation per unit area normal to this direction at the point considered, the power density, the spatial concentration of power. Total amount of time during exam that the sound is on. Dwell time x Duty Factor 3. Vibration maintained without interruption - more efficient heating.