Fr.: onde acoustique, ~ sonore
A type of → longitudinal wave that consists of mechanical → vibrations of small → amplitude propagated in an → elastic medium. Acoustic waves exhibit phenomena like → diffraction, → reflection, and → interference, but not → polarization. Also called → sonic and → sound waves. See also → acoustic wave equation. The branch of physics concerned with the properties of sonic waves is called → acoustics.
acoustic wave equation
hamugeš-e mowj-e sedâyi
Fr.: équation de l'onde acoustique
A → differential equation that describes the time evolution of the → scalar potential of the field φ. It is expressed by: ∇2φ = (1/c2)∂2φ/∂t2, where c is → velocity of → longitudinal waves and ∇2 is the → Laplacian operator.