In order to understand the correct situation in which to use the word affect or effect, the first thing one must do is have a clear understanding of what each word means. 1  Affect is usually used as a verb. It is an action word that means to produce a change in or influence something. 2  Effect is usually used as a noun.
Shear Factor. The distance a point moves due to shear divided by the perpendicular distance of a point from the invariant line.
The proportionality factor Î¼ in this formula is the viscosity (specifically, the dynamic viscosity) of the fluid. The ratio is called the rate of shear deformation or shear velocity, and is the derivative of the fluid speed in the direction perpendicular to the plates.he kinematic viscosity (also called momentum diffusivity) is the ratio of the dynamic viscosity Î¼ to the density of the fluid Ï. It is usually denoted by the Greek letter nu (Î½).