Dyne

dyne
dyne
Unit system	CGS units
Unit of	force
Symbol	dyn
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 (nanosthenes) 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
v t e	newton	dyne	kilogram-force, kilopond	pound-force	poundal
1 N	≡ 1 kg⋅m/s²	= 10⁵ dyn	≈ 0.10197 kp	≈ 0.22481 lb_F	≈ 7.2330 pdl
1 dyn	= 10⁻⁵ N	≡ 1 g⋅cm/s²	≈ 1.0197×10⁻⁶ kp	≈ 2.2481×10⁻⁶ lb_F	≈ 7.2330×10⁻⁵ pdl
1 kp	= 9.80665 N	= 980665 dyn	≡ g_n × 1 kg	≈ 2.2046 lb_F	≈ 70.932 pdl
1 lb_F	≈ 4.448222 N	≈ 444822 dyn	≈ 0.45359 kp	≡ g_n × 1 lb	≈ 32.174 pdl
1 pdl	≈ 0.138255 N	≈ 13825 dyn	≈ 0.014098 kp	≈ 0.031081 lb_F	≡ 1 lb⋅ft/s²
The value of g_n (9.80665 m/s²) as used in the official definition of the kilogram-force 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.)

References

^ 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.
^ Gyllenbok, Jan (11 April 2018). "dyne". Encyclopaedia of Historical Metrology, Weights, and Measures. Vol. 1. Birkhäuser. p. 90. ISBN 9783319575988. Retrieved 20 April 2018.
^ "Dyne". The New Student's Reference Work. Chicago: Compton. 1914.
^ 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.