Question

What is the magnitude of the coefficient of viscosity?

(a) Frictional force/Area

(b) Frictional force/ (Area* velocity gradient)

(c) Frictional force*Area

(d) Frictional force*Area/ velocity gradient

I had been asked this question in class test.

The doubt is from Methods of Determination of Coefficient of Viscosity in division Viscous Flow & Turbulent Flow of Fluid Mechanics

Answer 1

The correct choice is (b) Frictional force/ (Area* velocity gradient)

For explanation: Coefficient of viscosity is defined as the degree to which the fluid resists flow under an applied force. It is expressed as a ratio of shearing stress to the velocity gradient. It has a unit of Nsm^-2.