Digestion Essay The path of digestion begins in the mouth when food is broken down mechanically, into smaller pieces, by the teeth and tongue. The complex carbohydrates found in the food are also broken down chemically with the help of the enzyme (ptyalin), found in saliva.
apparent viscosity. (fluid mechanics). The value obtained by applying the instrumental equations used in obtaining the viscosity of a Newtonian fluid to viscometer measurements of a non-Newtonian fluid. 1  Facebook. 2  Twitter.
Freebase(0.00 / 0 votes)Rate this definition: Viscosity index is an arbitrary measure for the change of viscosity with temperature. It is used to characterize lubricating oil in the automotive industry. The viscosity of liquids decreases as temperature increases. The viscosity of a lubricant is closely related to its ability to reduce friction.