Sound energy

 ( Sound Measurements ) 

Sound energy is the energy carried by longitudinal mechanical waves in elastic media. The energy is periodically converted between kinetic energy and elastic potential energy of material points during the course of the wave's propagation. Only those waves that have a Audio frequency of 20 Hertz to 20 kHz are audible to humans. However, this range is an average and will slightly change from individual to individual. Sound waves that have frequencies below 20 Hz are called infrasound waves and those above 20 kHz are called ultrasound waves.

Consequently, the sound energy in a volume of interest is defined as the sum of the potential and kinetic energy density integrated over that volume:

$W\; =\; W\_\backslash mathrm\{potential\}\; +\; W\_\backslash mathrm\{kinetic\}\; =\; \backslash int\_V\; \backslash frac\{p^2\}\{2\; \backslash rho\_0\; c^2\}\backslash ,\; \backslash mathrm\{d\}V\; +\; \backslash int\_V\; \backslash frac\{\backslash rho\; v^2\}\{2\}\backslash ,\; \backslash mathrm\{d\}V,$

• V is the volume of interest;
• p is the sound pressure;
• v is the particle velocity;
• ρ₀ is the density of the medium without sound present;
• ρ is the local density of the medium; and
• c is the speed of sound.

• Sound energy density