Question

Define Viscosity.

(a) Resistance to flow of object

(b) Resistance to flow of air

(c) Resistance to flow of fluid

(d) Resistance to flow of heat

The question was posed to me by my college professor while I was bunking the class.

Origin of the question is Pipes in Series in division Flow Through Pipes of Fluid Mechanics

Answer 1

Correct choice is (c) Resistance to flow of fluid

For explanation I would say: Viscosity is developed due to the relative motion between two surfaces of fluids at different velocities. It happens due to the shear stress developed on the surface of the fluid.