The dyne (symbol: dyn; ) is a derived
unit of
force
In physics, a force is an influence that can cause an Physical object, object to change its velocity unless counterbalanced by other forces. In mechanics, force makes ideas like 'pushing' or 'pulling' mathematically precise. Because the Magnitu ...
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
The British Science Association (BSA) is a Charitable organization, charity and learned society founded in 1831 to aid in the promotion and development of science. Until 2009 it was known as the British Association for the Advancement of Scienc ...
.
Definition
The dyne is defined as "the force required to accelerate a
mass
Mass is an Intrinsic and extrinsic properties, intrinsic property of a physical body, body. It was traditionally believed to be related to the physical quantity, quantity of matter in a body, until the discovery of the atom and particle physi ...
of one
gram
The gram (originally gramme; SI unit symbol g) is a Physical unit, unit of mass in the International System of Units (SI) equal to one thousandth of a kilogram.
Originally defined in 1795 as "the absolute Mass versus weight, weight of a volume ...
at a rate of one
centimetre
upright=1.35, Different lengths as in respect to the electromagnetic spectrum, measured by the metre and its derived scales. The microwave is in-between 1 meter to 1 millimeter.
A centimetre (International spelling) or centimeter (American ...
per
second
The second (symbol: s) is a unit of time derived from the division of the day first into 24 hours, then to 60 minutes, and finally to 60 seconds each (24 × 60 × 60 = 86400). The current and formal definition in the International System of U ...
squared". 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".
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/s
2 = 10
−5 kg⋅m/s
2 = 10
−5 N
* 1 N = 1 kg⋅m/s
2 = 10
5 g⋅cm/s
2 = 10
5 dyn
Use
The dyne per centimetre is a unit traditionally used to measure
surface tension
Surface tension is the tendency of liquid surfaces at rest to shrink into the minimum surface area possible. Surface tension (physics), tension is what allows objects with a higher density than water such as razor blades and insects (e.g. Ge ...
. For example, the surface tension of distilled water is 71.99 dyn/cm at 25 °C (77 °F).
(In SI units this is or .)
See also
*
Centimetre–gram–second system of units
The centimetre–gram–second system of units (CGS or cgs) is a variant of the metric system based on the centimetre as the unit of length, the gram as the unit of mass, and the second as the unit of time. All CGS mechanical units are unamb ...
*
Erg
References
{{CGS units
Centimetre–gram–second system of units