Kinematic viscosity on the other hand is a measure of a fluid's resistance to flow and shear under the forces of gravity. Imperial units are either slugs per foot-second, or the equivalent pound-seconds per square foot. In practice the centiPoise is used since the Poise is a large unit. The metric unit for dynamic viscosity is dyne-second per square centimetre (or sometimes the numerically equivalent gram per centimetre-second is used) called a Poise (named after French physician and physiologist Jean Louis Marie Poiseuille). The larger the molecules, the higher the internal resistance and consequently the higher the dynamic viscosity. This internal friction is caused by the resistance of the fluid's molecules moving relative to each other. The dynamic viscosity (sometimes called absolute viscosity) of a fluid can be defined as the resistance to flow and shear under the forces of internal friction. We have a fluid with a shear rate of 0.5 s -1 and shearing stress of 0.76 N/m 2.Viscosity | Definitions and Convertions Dynamic Viscosity A small hole of area of cross-section… (NEET 2019).A rectangular film of liquid is extended from.(NEET 2016).A small sphere of radius ′r′ falls from rest in a viscous liquid.(NEET 2018).A fluid is in streamline flow across a horizontal pipe of variable area….(NEET 2013).A certain number of spherical drops of a liquid of radius… (NEET 2014).Water rises to a height h in capillary tube… (NEET 2015).The cylindrical tube of a spray pump has radius… (NEET 2015).A boat with scrap iron in it is floating in a small tank of water… (JIPMER 1998).A ball whose density is 0.4×103kg/m3 falls into water ….The bulk modulus of a fluid is inversely proportional to… (JIPMER 1996).The SI actual unit of dynamic viscosity (μ) is Pascal-second (Pa s), which also can be represented as 1 kg m -1 s -1.A rotary viscometer is a popular instrument, used to measure dynamic viscosity.The formula for the dynamic viscosity is given by η = Tγ.Dynamic viscosity is defined as the tangential force required to move one horizontal plane of a fluid with respect to another.Whereas, Kinetic Ciscosity is the representation of the inertia along with viscous force. Kinetic Viscosity can be represented as the ration between dynamic viscosity and density.ĭynamic Viscosity is the representation of the viscous force of the fluid. It is represented as the ratio between the sheer strees and sheer strain

The symbol of Kinetic Viscosity is v, and the unit of it is m 2/s The Symbol of Dynamic Viscosity is µ, and the unit of it is Ns/m 2 Whereas, Kinetic Viscosity is also know Absolute Viscosity. It can also be expressed as the tangential force per unit area required to move the fluid in a horizontal plane relative to another plane, with a unit value velocity while the molecules of the fluid maintain a distance unitary each on the other.ĭynamic Viscocity can also be known as Absolute Viscosity. Therefore, dynamic viscosity is the force required for fluid to overcome its internal molecular friction so that the fluid can flow. Viscosity acts as an important property of fluid when analyzing fluid behaviour and fluid movement near solid limits.It is a type of tangential force that acts when one horizontal plane moves with another.The dynamic viscosity formula for the fluid will define its internal resistance to flow due to shear force.Shear stress in the fluid is possible due to the intermolecular friction exerted when layers of fluids attempt to flow over each other. The viscosity of a fluid is the measure of the resistance to its progressive deformation by traction or shear.

Dynamic viscosity si units