Viscosity - Saylor Academy

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Viscosity1ViscosityViscosityClear liquid above has lower Viscosity than the substance belowSI symbol: , SI unit:Pa s = kg/(s m)Derivations from other quantities: = G tViscosity is a measure of the resistance of a fluid which is being deformed by either shear stress or tensile stress. Ineveryday terms (and for fluids only), Viscosity is "thickness" or "internal friction". Thus, water is "thin", having alower Viscosity , while honey is "thick", having a higher Viscosity . Put simply, the less viscous the fluid is, the greaterits ease of movement (fluidity).[1] Viscosity describes a fluid's internal resistance to flow and may be thought of as a measure of fluid friction.

A rheometer is used for those fluids which cannot be defined by a single value of viscosity and therefore require more parameters to be set and measured than is the case for a viscometer.

  Rheometer