Pascal (unit)
SI unit of pressure and stress
(Redirected from HPa)
The pascal (symbol: Pa) is the SI-derived unit of pressure or stress. It is a measure of perpendicular force per unit area and is equal to one newton per square meter. In everyday life, the pascal is best known from meteorological air-pressure reports, where it happens in the form of hectopascal (1 hPa = 100 Pa).[1] In other cases, the kilopascal is more commonly used such as on bicycle tire labels.[2] One hectopascal corresponds to 0.1 and one kilopascal to about 1% of atmospheric pressure (near sea level).
It is named after the French mathematician and physicist Blaise Pascal.
References
change- ↑ World Meteorological Organization: Manual on the Global Observing System – Volume I, Section 3.3.2.2: "The hectopascal (hPa), equal to 100 pascals (Pa), shall be the unit in which pressures are reported for meteorological purposes."
- ↑ ISO 5775: Bicycle tyres and rims
