# Power and Amplitude of sound wave

by Trooko
Tags: amplitude, power, sound, wave
 Admin P: 21,887 The displacement amplitude A is given by: $$A\,=\,\frac{\Delta{p_o}}{\omega\,\rho\,c}$$, where $\Delta{p_o}$ is the pressure amplitude, $\omega$ is the angular frequency given by $2\,\pi\,f$, $\rho$ is the material density, and c = speed of sound in the material, which is given by - $$c = \sqrt{\frac{E}{\rho}}$$ where E is Young's (Elastic) modulus. The intensity of the sound wave is I = P/a, where P is the power of the wave per unit transverse area, a, and P = 1/2 $\omega^2$A2$\rho$ c