# Pressure

Pressure (the symbol: p) is the ratio of force to the area over which that force is distributed. In other words, pressure is force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure (also spelled gage pressure) is the pressure relative to the local atmospheric or ambient pressure. While pressure may be measured in any unit of force divided by any unit of area, the SI unit of pressure (the newton per square metre) is called the pascal (Pa) after the seventeenth-century philosopher and scientist Blaise Pascal. A pressure of 1 Pa is small; it approximately equals the pressure exerted by a dollar bill resting flat on a table. Everyday pressures are often stated in kilopascals (1 kPa = 1000 Pa).

### Other articles related to "pressure, pressures":

Types - Kinematic Pressure
... is the kinematic pressure, where is the pressure and constant mass density ... Kinematic pressure is used in the same manner as kinematic viscosity in order to compute Navier-Stokes equation without explicitly showing the density ...
Pascal (unit)
... The pascal (symbol Pa) is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise ... On Earth, standard atmospheric pressure is 101 325 Pa ... Meteorological barometric pressure reports typically report atmospheric pressure in hectopascals ...
Pascal (unit) - Uses - Hectopascal and Millibar Units
... Meteorologists worldwide have for a long time measured atmospheric pressure in bars, which was originally equivalent to the average air pressure on Earth the bar was divided into a thousand ... introduction of SI units, many preferred to preserve the customary pressure figures ... the bar was redefined as 100,000 pascals, which is only slightly lower than standard air pressure on Earth ...
High Pressure
... High pressure in science and engineering is studying the effects of high pressure on materials and the design and construction of devices, such as a diamond anvil cell ... By high pressure it is usually meant pressures of thousands (kilobars) or millions (megabars) of times atmospheric pressure (about 1 bar or 100,000 Pa) ... received a Nobel prize for advancing this area of physics by several magnitudes of pressure (400 MPa to 40,000 MPa) ...
Pascal (unit) - Uses
... The pascal (Pa) or kilopascal (kPa) as a unit of pressure measurement is widely used throughout the world and has largely replaced the pounds per square inch (psi) unit, except in some countries that ... Other, older units of measure occasionally used for pressure are millimeters of mercury (Torr) and millimetres of water (1.0 mmH2O = 9.80665 Pa) ... In the cgs system, the unit of pressure is the barye (symbol ba), which is equal to one decipascal ...

### Famous quotes containing the word pressure:

This is a catastrophic universe, always; and subject to sudden reversals, upheavals, changes, cataclysms, with joy never anything but the song of substance under pressure forced into new forms and shapes.
Doris Lessing (b. 1919)

He who is of a calm and happy nature will hardly feel the pressure of age, but to him who is of an opposite disposition youth and age are equally a burden.
Plato (c. 427–347 B.C.)

By school age, many boys experience pressure to reveal inner feelings as humiliating. They think their mothers are saying to them, “You must be hiding something shameful.” And shucking clams is a snap compared to prying secrets out of a boy who’s decided to “clam up.”
Ron Taffel (20th century)