Pascal (unit)
The pascal (symbol: Pa) is the unit of pressure in the International System of Units (SI). It is also used to quantify internal pressure, stress, Young's modulus, and ultimate tensile strength. The unit, named after Blaise Pascal, is a SI coherent derived unit defined as one newton per square metre (N/m2). It is also equivalent to 10 barye (10 Ba) in the CGS system. 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.
| pascal | |
|---|---|
A pressure gauge reading in psi (red scale) and kPa (black scale) | |
| General information | |
| Unit system | SI |
| Unit of | pressure or stress |
| Symbol | Pa |
| Named after | Blaise Pascal |
| Conversions | |
| 1 Pa in ... | ... is equal to ... |
| SI base units: | kg⋅m−1⋅s−2 |
| US customary units: | 1.45038×10−4 psi |
| atmosphere: | 9.86923×10−6 atm |
| bar: | 10−5 bar |
| barye (CGS unit) | 10 Ba |
The unit of measurement called standard atmosphere (atm) is defined as 101,325 Pa. Meteorological observations typically report atmospheric pressure in hectopascals per the recommendation of the World Meteorological Organization, thus a standard atmosphere (atm) or typical sea-level air pressure is about 1013 hPa. Reports in the United States typically use inches of mercury or millibars (hectopascals). In Canada these reports are given in kilopascals.