They are introduced in the main books on hydrodynamics and rheology. There are several different viscosity coefficients depending on the nature of applied stress and nature of the fluid. When looking at a value for viscosity, the number that one most often sees is the coefficient of viscosity. A viscous glue was made from mistletoe berries and used for lime-twigs to catch birds. The word 'viscosity' derives from the Latin word ' viscum' for mistletoe.
5.1.1 Effect of temperature on the viscosity of a gas.4.1.3 Dynamic versus kinematic viscosity.4.1.1 Viscosity (dynamic/absolute viscosity).
