Their shear stress is proportional to the strain rate by a ratio known as the dynamic viscosity and the equation governing their motion in a pipe can 
Their shear stress is proportional to the strain rate by a ratio known as the dynamic viscosity and the equation governing their motion in a pipe can be derived from the Darcy-Weisbach law. When they flow between parallel plates with one plate fixed and the other moving, their motion is known as Couette flow and their flow through an annulus is similar to their motion through a hollow tube, known as Hagen-Poiseuille flow. Governed by the Navier-Stokes equations and by the equation "div V equals zero," FTP, identify these eponymous fluids whose viscosity does not vary with applied force.
Their shear stress is proportional to the strain rate by a ratio known as the dynamic viscosity and the equation governing their motion in a pipe can be derived from the Darcy-Weisbach law.
Newtonian fluids