âºâº Definition: Second. A second of arc or arcsecond is a unit of angular measurement which comprises one-sixtieth of an arcminute, or 1/3600 of a degree of arc or 1/1296000 (approximately 7.710-7) of a circle.
The resistance of a liquid to flowing is its viscosity.   Viscosity is a property arising from friction between  neighboring particles in a fluid that are moving at dif â¦ ferent  velocities. In liquids, it could be considered the thickness.
Choked flow is a fluid dynamic condition associated with the Venturi effect. When a flowing fluid at a given pressure and temperature passes through a restriction (such as the throat of a convergent-divergent nozzle or a valve in a pipe) into a lower pressure environment the fluid velocity increases.