Ans: Some materials such as toothpastes and mayonnaise** **can resist a finite shear stress behaving like a solid but deform continuously when shear stress exceeds the yield stress and starting behaving as fluids.

These are the non-Newtonian fluids i.e. the relationship between shear stress and shear strain rate is **non-linear**.

The following video shows an example and demonstration of the Bingham plastic fluid.