Search results
Results from the WOW.Com Content Network
The unit, named after Blaise Pascal, is an SI coherent derived unit defined as one newton per square metre (N/m 2). [1] 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 ...
The standard atmosphere (symbol: atm) is a unit of pressure defined as 101,325 Pa (1,013.25 hPa), which is equivalent to 1,013.25 millibars, [1] 760 mm Hg, 29.9212 inches Hg, or 14.696 psi. [2] The atm unit is roughly equivalent to the mean sea-level atmospheric pressure on Earth; that is, the Earth's atmospheric pressure at sea level is ...
The standard atmosphere was originally defined as the pressure exerted by a 760 mm column of mercury at 0 °C (32 °F) and standard gravity (g n = 9.806 65 m/s 2). [2] It was used as a reference condition for physical and chemical properties, and the definition of the centigrade temperature scale set 100 °C as the boiling point of water at this pressure.
Name of unit Symbol Definition Relation to SI units atmosphere-cubic centimetre per minute: atm ccm [citation needed] ≡ 1 atm × 1 cm 3 /min = 1.688 75 × 10 −3 W: atmosphere-cubic centimetre per second: atm ccs [citation needed] ≡ 1 atm × 1 cm 3 /s = 0.101 325 W: atmosphere-cubic foot per hour: atm cfh [citation needed] ≡ 1 atm × 1 ...
The SI unit for pressure is the pascal (Pa), equal to one newton per square metre (N/m 2, or kg·m −1 ·s −2). This name for the unit was added in 1971; [7] before that, pressure in SI was expressed in newtons per square metre. Other units of pressure, such as pounds per square inch (lbf/in 2) and bar, are also in common use.
At standard mean sea level it specifies a temperature of 15 °C (59 °F), pressure of 101,325 pascals (14.6959 psi) (1 atm), and a density of 1.2250 kilograms per cubic meter (0.07647 lb/cu ft). It also specifies a temperature lapse rate of −6.5 °C (−11.7 °F) per km (approximately −2 °C (−3.6 °F) per 1,000 ft).
This use of the unit of pressure provides an intuitive understanding for how a body's mass, in contexts with roughly standard gravity, can apply force to a scale's surface area, i.e. kilogram-force per square (centi-)metre. In SI units, the unit is converted to the SI derived unit pascal (Pa), which is defined as one newton per square metre (N ...
Pressure units Pascal Bar Technical atmosphere Standard atmosphere Torr ... 1 atm ≡ 101 325: ≡ 1.013 25: 1.0332 — 760 14.695 948 775 5142: 1 Torr