Question

Fluids which undergo strain rates proportional to the applied shear stress are termed as?

(a) Inviscid fluid

(b) Newtonian fluid

(c) Non- Newtonian fluid

(d) Viscous fluid

The question was asked during an online exam.

My enquiry is from Classification of Fluids in chapter Fluid Flow and Mixing of Bioprocess Engineering

Answer 1

Right option is (b) Newtonian fluid

Explanation: Newtonian fluids undergo strain rates proportional to the applied shear stress. It is defined to be a fluid whose shear stress is linearly proportional to the velocity gradient in the direction perpendicular to the plane of shear. This definition means regardless of the forces acting on a fluid, it continues to flow.