Pascal (unit) Pascal (unit) The pascal (symbol: Pa) is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength. It is defined as one newton per square metre. It is named after the French polymath Blaise Pascal. Common multiple units of the pascal are the hectopascal (1 hPa = 100 Pa) which is equal to one millibar, and the kilopascal (1 kPa = 1000 Pa) which is equal to one centibar. The unit of measurement called standard atmosphere (atm) is defined as . Meteorological reports typically state atmospheric pressure in millibars. The unit is
Poise (unit) The abbreviations cps, cp, and cPs are sometimes seen. Liquid water has a viscosity of 0.00890 P at 25 °C and a pressure of 1 atmosphere (0.00890 P = 0.890 cP = 0.890 mPa⋅s). Poise (unit) The poise (symbol P; ) is the unit of dynamic viscosity (absolute viscosity) in the centimetre–gram–second system of units. It is named after Jean Léonard Marie Poiseuille (see Hagen–Poiseuille equation). The analogous unit in the International System of Units is the pascal-second (Pa⋅s): The poise is often used with the metric prefix "centi-" because the viscosity of water at 20 °C (NTP) is almost