Question

What is the viscosity of water at 30^oC?

(a) 80.1

(b) 0.801

(c) 801

(d) 0.081

The question was posed to me at a job interview.

Origin of the question is Basic Equations of Compressible Flow topic in section Compressible Flow of Fluid Mechanics

Answer 1

The correct option is (b) 0.801

For explanation: A graph is plotted with temperature in the x-axis and dynamic viscosity in the y-axis. With the increase in pressure the viscosity decreases. It corresponds to an informal concept of thickness.