Written by the Fiveable Content Team โข Last updated August 2025
Verified for the 2026 exam
Verified for the 2026 examโขWritten by the Fiveable Content Team โข Last updated August 2025
Definition
Viscosity refers to the measure of a fluid's resistance to flow. It describes how thick or sticky a fluid is, and determines how easily it can be poured or moved.
Shear Stress: Shear stress is the force per unit area that causes one layer of fluid to slide past another layer. It is directly related to viscosity.
Newtonian Fluid: A Newtonian fluid is a type of fluid that follows Newton's law of viscosity, where the shear stress is directly proportional to the rate of deformation.
Non-Newtonian Fluid: A non-Newtonian fluid does not follow Newton's law of viscosity and its behavior depends on factors like pressure, temperature, or applied force. Examples include ketchup and toothpaste.