Newtonian fluid

A Newtonian fluid is a fluid, where the ratio between shear stress changes linearly in proportion to the stress it is exposed to. This proportion is known as viscosity. Note that the inverse is not true; there are fluids with constant viscosity, that are Non-Newtonian fluids: one example is the Boger fluid.

Mechanics

Laws Conservation of mass Conservation of momentum Conservation of energy Entropy inequality Solid mechanics Solids Stress · Deformation Compatibility Finite strain · Infinitesimal strain Elasticity (linear) · Plasticity Bending · Hooke's law Failure theory Fracture mechanics Frictionless/Frictional Contact mechanics Fluid mechanics Fluids Fluid statics · Fluid dynamics Surface tension Navier–Stokes equations Viscosity: Newtonian, Non-Newtonian Rheology Viscoelasticity Smart fluids: Magnetorheological Electrorheological Ferrofluids Rheometry · Rheometer Scientists Bernoulli · Cauchy · Hooke Navier · Newton · Stokes