# Thin-wire wave speed

A material property: the speed at which a pressure wave travels along a thin wire. The thin-wire wave speed is related to other material properties by —

\begin{align} \label{eq:12401a} c_{tw} &= \left[ \frac{E}{\rho} \right]^{1/2} \, \end{align}

where —

 $$c_{tw}$$ = thin-wire wave speed $$E$$ = modulus of elasticity (Young's modulus) $$\rho$$ = density

Most acoustic materials have a thin-wire wave speed between 4700 and 5300 m/sec. The thin-wire wave speed decreases with increasing temperature.

The thin-wire wave speed is related to the thin-wire half-wavelength by —

\begin{align} \label{eq:12402a} c_{tw} = 2 \, \Gamma_{tw} \, f \end{align}

where —

 $$f$$ = resonant frequency $$\Gamma_{tw}$$ = thin-wire half-wavelength at the specified frequency

The thin-wire wave speed, along with the resonator dimensions and shape, determines the resonant frequency.

Reference: Meyer (1), equation 1.61, p. 19