# What is pressure?

• (noun): The force applied to a unit area of surface; measured in pascals (SI unit) or in dynes (cgs unit).
Example: "The compressed gas exerts an increased pressure"
Synonyms: pressure level, force per unit area

## 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).

### Some articles on pressure:

Pascal (unit) - Uses - Hectopascal and Millibar Units
... 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 millibars to provide the precision ... units, many preferred to preserve the customary pressure figures ... 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, which ... 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) ... this area of physics by several magnitudes of pressure (400 MPa to 40,000 MPa) ...
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) - Uses
... 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 ... 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 ...
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 ... On Earth, standard atmospheric pressure is 101 325 Pa ... Meteorological barometric pressure reports typically report atmospheric pressure in hectopascals ...

### More definitions of "pressure":

• (noun): A force that compels.
Example: "The public brought pressure to bear on the government"
• (noun): The somatic sensation of pressure.
Example: "The sensitivity of his skin to pressure and temperature was normal"
Synonyms: pressure sensation
• (noun): The act of pressing; the exertion of pressure.
Example: "He used pressure to stop the bleeding"
Synonyms: press, pressing
• (verb): .
Example: "To cause to do through pressure or necessity, by physical, moral or intellectual means :"She forced him to take a job in the city"
Synonyms: coerce, hale, squeeze, force
• (noun): An oppressive condition of physical or mental or social or economic distress.

### Famous quotes containing the word pressure:

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.)

Destiny is an absolutely definite and inexorable ruler. Physical ability and moral determination count for nothing. It is impossible to perform the simplest act when the gods say “no.” I have no idea how they bring pressure to bear on such occasions; I only know that it is irresistible.
Aleister Crowley (1875–1947)

Under the pressure of the cares and sorrows of our mortal condition, men have at all times, and in all countries, called in some physical aid to their moral consolations—wine, beer, opium, brandy, or tobacco.
Edmund Burke (1729–1797)