Wave Impedance

The wave impedance

represents the medium's resitance to distortion in the presence of an external force;
a characteristic of the medium in which a wave propagates and given by:

$\displaystyle Z = \frac{F}{v} = \frac{p}{U},$

$\displaystyle v$ $\displaystyle \triangleq$ particle velocity;

$\displaystyle p =F/A$ $\displaystyle \triangleq$ acoustic pressure;

$\displaystyle U=v/A$ $\displaystyle \triangleq$ volume velocity (airflow);

$\displaystyle A$ $\displaystyle \triangleq$ medium cross-sectional area $\displaystyle .$

For solids,

$\displaystyle Z_0 = \rho c,$

where $\rho$ is the density of the material.

For gases in cylindrical tubes with a cross sectional area of ,

$\displaystyle Z_0 = \frac{\rho c}{A}.$

``Music 206: Digital Waveguides'' by Tamara Smyth, Department of Music, University of California, San Diego (UCSD).

$\displaystyle v$	$\displaystyle \triangleq$	particle velocity;
$\displaystyle p =F/A$	$\displaystyle \triangleq$	acoustic pressure;
$\displaystyle U=v/A$	$\displaystyle \triangleq$	volume velocity (airflow);
$\displaystyle A$	$\displaystyle \triangleq$	medium cross-sectional area $\displaystyle .$