First-order fluid
= First-order fluid
{wiki=First-order_fluid}
A first-order fluid, also known as a Newtonian fluid, is a type of fluid that adheres to Newton's law of viscosity. This means that the fluid's shear stress is directly proportional to the shear rate (or velocity gradient) at a given temperature and pressure. Mathematically, this relationship is represented as: \\\[ \\tau = \\mu \\frac\{du\}\{dy\} \\\] Where: - \\(\\tau\\) is the shear stress.