Question

Which of the following is shear thinning fluid?

(a) Pseudoplastic

(b) Dilatant

(c) Rheopectic

(d) Bingham plastic

I got this question at a job interview.

The above asked question is from Non Newtonian Fluids topic in chapter Fluid Flow and Mixing of Bioprocess Engineering

Answer 1

Right option is (a) Pseudoplastic

The explanation is: In rheology, shear thinning is the non-Newtonian behavior of fluids whose viscosity decreases under shear strain. It is sometimes considered synonymous for pseudoplastic behaviour, and is usually defined as excluding time-dependent effects, such as thixotropy. Shear-thinning behaviour is generally not seen in pure liquids with low molecular mass, or ideal solutions of small molecules like sucrose or sodium chloride, but is often seen in polymer solutions and molten polymers, and complex fluids and suspensions like ketchup, whipped cream, blood, paint, and nail polish.