Mach wave (angle)
In fluid dynamics, a Mach wave is a pressure wave traveling with the speed of sound caused by a slight change of pressure added to a compressible flow.
Darcy's law (simplified)
Darcy’s law states that the volume of flow of the pore fluid through a porous medium per unit time is proportional to the rate of change of excess
Escape velocity is the speed at which the kinetic energy plus the gravitational potential energy of an object is zero. It is the speed needed to
Amount of Substance
Amount of substance (n) is the number of atoms, molecules, ions, or other specified group of entities present in a compound. It is the ratio of Mass /
Hartmann number (Ha) is the ratio of electromagnetic force to the viscous force first introduced by Hartmann.