Kilogram-force: Difference between revisions

From Citizendium
Jump to navigation Jump to search
imported>Milton Beychok
m (Added some notes)
imported>Milton Beychok
m (Added a reference)
Line 1: Line 1:
{{subpages}}
{{subpages}}
A '''kilogram-force''' ('''kgf''') is a [[Measurement|measurement]] unit of [[force]] which will [[acceleration|accelerate]] 1 [[kilogram]] of [[mass]] to 9.80665 [[metre|m]]/[[second|s]]<sup>2</sup>, the standard average [[acceleration due to gravity]] on [[Earth]]'s surface (referred to as '''''g<sub>n</sub>''''').<ref name=NIST-gravity/> Since a [[Newton (unit)|newton]] is defined<ref name=NASA/><ref name=NIST-newton/> as the force which will accelerate 1 kilogram  of mass to 1 m/s<sup>2</sup>, one  kilogram-force is by definition equal to 9.80665 [[newton (unit)|newtons]]. The kilogram-force is often referred to as the '''''kilopond (kp)'''''.<ref name=kp group=note/>
A '''kilogram-force''' ('''kgf''') is a [[Measurement|measurement]] unit of [[force]] which will [[acceleration|accelerate]] 1 [[kilogram]] of [[mass]] to 9.80665 [[metre|m]]/[[second|s]]<sup>2</sup>, the standard average [[acceleration due to gravity]] on [[Earth]]'s surface (referred to as '''''g<sub>n</sub>''''').<ref name=NIST-gravity/> Since a [[Newton (unit)|newton]] is defined<ref name=NASA/><ref name=NIST-newton/> as the force which will accelerate 1 kilogram  of mass to 1 m/s<sup>2</sup>, one  kilogram-force is by definition equal to 9.80665 [[newton (unit)|newtons]].<ref name=NIST-kgf/> The kilogram-force is often referred to as the '''''kilopond (kp)'''''.<ref name=kp group=note/>


The kilogram-force was not very well defined until the 3rd [[General Conference on Weights and Measures]] (Conférence Générale des Poids et Mesures, CGPM) defined '''''g<sub>n</sub>''''', the standard gravity, to be 9.80665 m/s<sup>2</sup> in 1901.<ref name=GCPM3/> Although it was once widely used, it has never been part of the [[International System of Units]] (SI) introduced in 1960 by the 11th GCPM.<ref name=GCPM11/>
The kilogram-force was not very well defined until the 3rd [[General Conference on Weights and Measures]] (Conférence Générale des Poids et Mesures, CGPM) defined '''''g<sub>n</sub>''''', the standard gravity, to be 9.80665 m/s<sup>2</sup> in 1901.<ref name=GCPM3/> Although it was once widely used, it has never been part of the [[International System of Units]] (SI) introduced in 1960 by the 11th GCPM.<ref name=GCPM11/>
Line 26: Line 26:
==References==
==References==
{{Reflist|refs=
{{Reflist|refs=
<ref name=NIST-kgf>[http://wtc.nist.gov/progress_report_june04/metric_conversion.pdf Metric Conversion Table] Scroll down to "Force"</ref>


<ref name=NIST-gravity>[http://physics.nist.gov/Pubs/SP330/sp330.pdf The International System of Units (SI), NIST Special Publication 330, 2008 Edition] (pdf page 57 of 77 pdf pages)</ref>
<ref name=NIST-gravity>[http://physics.nist.gov/Pubs/SP330/sp330.pdf The International System of Units (SI), NIST Special Publication 330, 2008 Edition] (pdf page 57 of 77 pdf pages)</ref>

Revision as of 22:42, 5 July 2011

This article is developing and not approved.
Main Article
Discussion
Related Articles  [?]
Bibliography  [?]
External Links  [?]
Citable Version  [?]
 
This editable Main Article is under development and subject to a disclaimer.

A kilogram-force (kgf) is a measurement unit of force which will accelerate 1 kilogram of mass to 9.80665 m/s2, the standard average acceleration due to gravity on Earth's surface (referred to as gn).[1] Since a newton is defined[2][3] as the force which will accelerate 1 kilogram of mass to 1 m/s2, one kilogram-force is by definition equal to 9.80665 newtons.[4] The kilogram-force is often referred to as the kilopond (kp).[note 1]

The kilogram-force was not very well defined until the 3rd General Conference on Weights and Measures (Conférence Générale des Poids et Mesures, CGPM) defined gn, the standard gravity, to be 9.80665 m/s2 in 1901.[5] Although it was once widely used, it has never been part of the International System of Units (SI) introduced in 1960 by the 11th GCPM.[6]

The kilogram-force is still used to some extent in a few countries, but it is generally considered to be obsolete in most countries.

Equivalent units of force

  • 1 kgf ≡ 9.80665 newton (symbol: N)
  • 1 kgf ≡ 980,665 dyne (symbol: dyn)
  • 1 kgf ≡ 1 kilopond (symbol: kp)[note 1]
  • 1 kgf ≡ 9.80665×10-3 sthène (symbol: sn)
  • 1 kgf ≈ 2.20462 pound-force (symbol: lbf)
  • 1 kgf ≈ 2.20462×10-3 kip (symbol: kip)[note 2]
  • 1 kgf ≈ 70.93164 poundal (symbol: pdl)

Notes

  1. 1.0 1.1 Another name for a kilogram-force. Not to be confused with "kilopounds", meaning 1,000 pounds of mass.
  2. A non-SI unit of force equal to 1,000 pound-force.

References