Poise (unit)
| poise | |
|---|---|
| Unit system | Centimetre–gram–second system of units |
| Unit of | Dynamic viscosity |
| Symbol | P |
| Named after | Jean Léonard Marie Poiseuille |
| Derivation | 1 P = 1 dyn⋅s/cm2 |
| Conversions | |
| 1 Pin... | ... is equal to... |
| CGS base units | 1 cm−1⋅g⋅s−1 |
| SI units | 0.1 Pa⋅s |
Thepoise(symbolP;/pɔɪz,pwɑːz/) is the unit ofdynamic viscosity(absolute viscosity) in thecentimetre–gram–second system of units(CGS).[1]It is named afterJean Léonard Marie Poiseuille(seeHagen–Poiseuille equation). Thecentipoise(1 cP = 0.01 P) is more commonly used than the poise itself.
Dynamic viscosity has dimensions of,that is,.
![{\displaystyle [{\mathsf {M}}^{1}{\mathsf {L}}^{-1}{\mathsf {T}}^{-1}]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/e4e00a7e8b4e08a7fb7e609f10ea7f577adf8feb)
The analogous unit in theInternational System of Unitsis thepascal-second(Pa⋅s):[2]
The poise is often used with themetric prefixcenti-because the viscosity of water at 20 °C (standard conditions for temperature and pressure) is almost exactly 1 centipoise.[3]A centipoise is one hundredth of a poise, or one millipascal-second (mPa⋅s) in SI units (1 cP = 10−3Pa⋅s = 1 mPa⋅s).[4]
The CGS symbol for the centipoise is cP. The abbreviations cps, cp, and cPs are sometimes seen.
Liquid water has a viscosity of 0.00890 P at 25 °C at a pressure of 1atmosphere(0.00890 P = 0.890 cP = 0.890 mPa⋅s).[5]
See also
[edit]
References
[edit]- ^Gooch, Jan W. (2010).Encyclopedia dictionary of polymers(2nd ed.). Berlin: Springer.ISBN978-1-4419-6246-1.
- ^Reid, Robert C. (1987).The Properties of Gases and Liquids(4th ed.). McGraw-Hill.
- ^Parker, Sybil P. (1988).Fluid Mechanics Source Book(1st ed.). McGraw-Hill.
- ^Lide, David R. (1994).CRC Handbook of Thermophysical and Thermochemical Data(1st ed.). CRC Press.
- ^"Viscosity of Liquids", in CRC Handbook of Chemistry and Physics, 91st Edition, W.M. Haynes, ed., CRC Press/Taylor and Francis, Boca Raton, Florida, 2010-2011.