This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Pressure wave.svg en Diagram showing control volume surrounding an infinitesimal pressure wave traveling from left to right thus seeing an incoming velocity from the right This analysis is used to derive an expression for the speed of sound as function of the fluid other properties own Olivier Cleynen other versions cczero Uploaded