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dyne
Unit system CGS units
Unit of force
Symboldyn
Conversions
1 dyn in ...... is equal to ...
   CGS base units   1 g⋅cm/s2
   SI units   10−5 N
    British Gravitational System   2.248089×10−6 lbf

The dyne (symbol: dyn; from Ancient Greek δύναμις (dúnamis) 'power, force') is a derived unit of force specified in the centimetre–gram–second (CGS) system of units, a predecessor of the modern SI.

History

The name dyne was first proposed as a CGS unit of force in 1873 by a Committee of the British Association for the Advancement of Science. [1]

Definition

The dyne is defined as "the force required to accelerate a mass of one gram at a rate of one centimetre per second squared". [2] An equivalent definition of the dyne is "that force which, acting for one second, will produce a change of velocity of one centimetre per second in a mass of one gram". [3]

One dyne is equal to 10 micronewtons, 10−5 N or to 10 nsn (nano sthenes) in the old metre–tonne–second system of units.

  • 1 dyn = 1 g⋅cm/s2 = 10−5 kg⋅m/s2 = 10−5 N
  • 1 N = 1 kg⋅m/s2 = 105 g⋅cm/s2 = 105 dyn
Units of force
newton dyne kilogram-force,
kilopond
pound-force poundal
1 N ≡ 1 kg⋅m/s2 = 105 dyn ≈ 0.10197 kp ≈ 0.22481 lbf ≈ 7.2330 pdl
1 dyn = 10–5 N  1 g⋅cm/s2  1.0197×10−6 kp  2.2481×10−6 lbf  7.2330×10−5 pdl
1 kp = 9.80665 N = 980665 dyn  gn × 1 kg  2.2046 lbf  70.932 pdl
1 lbf  4.448222 N  444822 dyn  0.45359 kp  gn × 1  lb  32.174 pdl 
1 pdl  0.138255 N  13825 dyn  0.014098 kp  0.031081 lbf  1 lb⋅ ft/s2
The value of gn as used in the official definition of the kilogram-force (9.80665 m/s2) is used here for all gravitational units.

Use

The dyne per centimetre is a unit traditionally used to measure surface tension. For example, the surface tension of distilled water is 71.99 dyn/cm at 25 °C (77 °F). [4] (In SI units this is 71.99×10−3 N/m or 71.99 mN/m.)

See also

References

  1. ^ Thomson, Sir Wl; Professor GC, Foster; Maxwell, Professor JC; Stoney, Mr GJ; Professor Flemming, Jenkin; Siemens, Dr; Bramwell, Mr FJ (September 1873). Everett, Professor (ed.). First Report of the Committee for the Selection and Nomenclature of Dynamical and Electrical Units. Forty-third Meeting of the British Association for the Advancement of Science. Bradford: Johna Murray. p. 224. Retrieved 8 April 2012.
  2. ^ Gyllenbok, Jan (11 April 2018). "dyne". Encyclopaedia of Historical Metrology, Weights, and Measures. Vol. 1. Birkhäuser. p. 90. ISBN  9783319575988. Retrieved 20 April 2018.
  3. ^ "Dyne". The New Student's Reference Work. Chicago: Compton. 1914.
  4. ^ Haynes, W.M.; Lide, D. R.; Bruno, T.J., eds. (2015). "Surface tension of common liquids". CRC Handbook of Chemistry and Physics (96nd ed.). CRC Press. p. 6-181. ISBN  9781482260977.