Newtonian fluid

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Scientists Bernoulli Boyle Cauchy Charles Euler Gay-Lussac Hooke Pascal Newton Navier Stokes

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.