What is the relationship between shear stress and shear rate in fluid mechanics?
In fluid mechanics, shear stress is the force per unit area applied parallel to the surface of a fluid, while shear rate is the rate at which adjacent layers of fluid move past each other. The relationship between shear stress and shear rate is described by Newton's law of viscosity, which states that shear stress is directly proportional to shear rate. This means that as the shear rate increases, the shear stress also increases proportionally.