Measure visocity of water by poises

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Viscosity of water is measured in poises, with the standard unit commonly used being centipoise, where 1 cp equals 0.001 Pa·s. Viscosity represents a fluid's resistance to flow and is defined as the internal friction within the fluid when subjected to shear stress. The relationship between shear stress and viscosity is expressed mathematically, indicating that viscosity is not related to atmospheric pressure but rather to applied shear stress. Additionally, viscosity can be understood as a measure of a fluid's ability to resist deformation under stress. Understanding these concepts is crucial for accurately interpreting fluid behavior in various applications.
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i read that you measure visocity of water by poises (sounds like poison :rolleyes: ), how does it equate with the quantities?
i.e, like [N]=[kg*m^2/sec]
 
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For most applications, the standard is in centipoise.

1 cp = .001 Pa*sec or 1.45 x10^-7 Lbf*sec/ft^2 for us non SI'ers.

BTW...a Newton is \frac{kg*m}{sec^2}
 
Pa*sec is pascal times seconds, right?
so visocity of liquids is actually the atmospheric presure against time, or in other words how do you explain to a layperson what visocity of liquids is?
 
In the most basic sense: Viscosity = resistance to flow. If you want to go a bit farther, viscosity is a measure of the ability of a fluid to resist shear stress.

You have to be careful in interpreting the units for viscosity. The pressure is not atmospheric pressure. It is shear stress. The mathematical relation for viscosity is:

\tau = \mu \frac{du}{dy}

Where:
\tau = shear stress
\mu = viscosity
\frac{du}{dy} = velocity distribution
 
http://en.wikipedia.org/wiki/Viscosity
Viscosity is a measure of the resistance of a fluid to deformation under shear stress.
Wikipedia

Viscosity is commonly perceived as "thickness", or resistance to pouring, however it really describes a fluid's internal resistance to flow and may be thought of as a measure of fluid friction. Adapted from Wikipedia.

Solids exhibit viscosity when subject to very high compressive or tensile stresses, e.g. extrusion or other forms of cold or hot working.

The pressure is not necessarily atmospheric pressure, but applied pressure, and this more a case that the term is in units of pressure. This expression refers to kinematic viscosity \nu vs dynamic viscosity \mu, which have the following relationship

\nu = \mu/\rho
 
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