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The '''kilogram-force per square centimeter''' (symbol: '''kgf/cm<sup>2</sup>''' or often just '''kg/cm<sup>2</sup>''') is a unit of [[pressure]]. It is the [[force]] exerted by one [[kilogram-force]] on one square [[centimeter]]. | |||
Although the kgf utilizes metric units and was once widely used, it has never been part of the modern [[International System of Units]] (SI) introduced in 1960 by the ''11th Conférence Générale des Poids et Mesures (CGPM)''.<ref name=GCPM11/> It is still used to some extent in a few countries, but is generally considered to be obsolete in most countries. The kgf is sometimes referred to as the '''kilopond per square centimeter''' (symbol: '''kp/cm<sup>2</sup>''') or as the '''technical atmosphere''' (symbol: '''at'''). | |||
1 kgf equals exactly 98,066.5 Pa, where [[pascal (unit)|pascal]] (Pa) is the modern [[SI]] unit of pressure. | |||
==Other pressure units and equivalents== | |||
{{main|Pressure}} | |||
{{pressure}}<br/> | |||
'''About the torr:''' There is no consensus in the technical literature about whether the name of the torr should be "Torr" or "torr". Nor is there any consensus about whether the symbol for that unit of pressure should be "Torr" or "torr". Both the [[United Kingdom]]'s [[National Physical Laboratory]] (see [http://www.npl.co.uk/reference/faqs/pressure-units Pressure Units]) and [[New Zealand]]'s [[Measurement Standards Laboratory]] (see [http://msl.irl.cri.nz/sites/all/files/training-manuals/TG19-July-2009.pdf Barometric Pressure Units]) use "torr" as the name and as the symbol. An extensive search of the website of the [[U.S.]] [[National Institute of Standards and Technology]] found no such clear-cut definitions. Therefore, this table uses "torr" as both the name and the symbol. | |||
==References== | |||
{{reflist|refs= | |||
<ref name=GCPM11>[http://www.bipm.org/en/CGPM/db/11/12/ Resolution 12 of the 11th meeting of the CGPM (1960)] The resolution by the Conférence Générale des Poids et Mesures that created the modern International System of Units (SI).</ref> | |||
}} | |||
Revision as of 14:29, 8 July 2011
The kilogram-force per square centimeter (symbol: kgf/cm2 or often just kg/cm2) is a unit of pressure. It is the force exerted by one kilogram-force on one square centimeter.
Although the kgf utilizes metric units and was once widely used, it has never been part of the modern International System of Units (SI) introduced in 1960 by the 11th Conférence Générale des Poids et Mesures (CGPM).[1] It is still used to some extent in a few countries, but is generally considered to be obsolete in most countries. The kgf is sometimes referred to as the kilopond per square centimeter (symbol: kp/cm2) or as the technical atmosphere (symbol: at).
1 kgf equals exactly 98,066.5 Pa, where pascal (Pa) is the modern SI unit of pressure.
Other pressure units and equivalents
| pascal (Pa) |
bar (bar) |
atmosphere (atm) |
torr (torr) |
pound-force per square inch (psi) |
kilogram-force per square centimeter (kgf/cm2) | |
|---|---|---|---|---|---|---|
| 1 Pa | ≡ 1 N/m2 | 10−5 | 9.8692×10−6 | 7.5006×10−3 | 145.04×10−6 | 1.01972×10−5 |
| 1 bar | 100,000 | ≡ 106 dyn/cm2 | 0.98692 | 750.06 | 14.504 | 1.01972 |
| 1 atm | 101,325 | 1.01325 | ≡ 1 atm | 760 | 14.696 | 1.03323 |
| 1 torr | 133.322 | 1.3332×10−3 | 1.3158×10−3 | ≡ 1 torr ≈ 1 mmHg |
19.337×10−3 | 1.35951×10−3 |
| 1 psi | 6,894.76 | 68.948×10−3 | 68.046×10−3 | 51.715 | ≡ 1 lbf/in2 | 7.03059×10−2 |
| 1 kgf/cm2 | 98,066.5 | 0.980665 | 0.967838 | 735.5576 | 14.22357 | ≡ 1 kgf/cm2 |
Example reading: 1 Pa = 1 N/m2 = 10−5 bar = 9.8692×10−6 atm = 7.5006×10−3 torr, etc.
Note: mmHg is an abbreviation for millimetre of mercury
About the torr: There is no consensus in the technical literature about whether the name of the torr should be "Torr" or "torr". Nor is there any consensus about whether the symbol for that unit of pressure should be "Torr" or "torr". Both the United Kingdom's National Physical Laboratory (see Pressure Units) and New Zealand's Measurement Standards Laboratory (see Barometric Pressure Units) use "torr" as the name and as the symbol. An extensive search of the website of the U.S. National Institute of Standards and Technology found no such clear-cut definitions. Therefore, this table uses "torr" as both the name and the symbol.
References
- ↑ Resolution 12 of the 11th meeting of the CGPM (1960) The resolution by the Conférence Générale des Poids et Mesures that created the modern International System of Units (SI).