The maximum increase in pressure in the medium due to the presence of a sound wave is called sound pressure. Pressure is the amount of force acting over a 1 cm unit area of surface. Sound pressure is normally expressed in dynes/cm2 or microbar (ubar). The next formulas describe relationships between sound presuire and the maximum velocity of vibration of particles;


Formula 1

Sound pressure x vibration of particles

P = V x Z



P is the sound pressurein ubar

V is the velocity of vibration in centimeters per second

Z is the specific acoustic resistance in g/cm2s