Variables

Definition

Unit

p

Sound pressure at a given point at a given time

Pa

$p_0$

The maximum sound pressure of the sound wave

Pa

$\omega$

Angular frequency of the sound wave

s⁻¹

$c_0$

Speed of sound in a given medium

m∙s⁻¹

u

Change in velocity of the medium due to sound at a given time

m∙s⁻¹

$u_0$

Maximum change in velocity of the medium due to the sound wave

m∙s⁻¹

${\rho }_0$

Density of the medium under steady condition

kg∙m⁻³

k

Wave number

m⁻¹

Ω

Energy flux density in direction of the sound wave

W∙m⁻²

I

Sound intensity

W∙m⁻²

T

The period of the sound wave

s

$Z_a$

Characteristic impedance of sound of a certain material

kg∙m⁻²∙s⁻¹

$p_{i,r,t}$

Sound pressure due to the incident, reflected, or transmitted wave

Pa

$I_{i,r,t}$

Sound pressure due to the incident, reflected, or transmitted wave

W∙m⁻²

${\theta }_{i,r,t}$

Angle of incidence, reflection, or refraction

Radians

$R_{p,u,I}$

Coefficient of reflection of sound pressure, velocity, or intensity

No unit

$D_{p,u,I}$

Coefficient of transmission of sound pressure, velocity, or intensity

No unit