The dyne (symbol: dyn; ) is a derived
unit
Unit may refer to:
Arts and entertainment
* UNIT, a fictional military organization in the science fiction television series ''Doctor Who''
* Unit of action, a discrete piece of action (or beat) in a theatrical presentation
Music
* ''Unit'' (a ...
of
force
In physics, a force is an influence that can change the motion of an object. A force can cause an object with mass to change its velocity (e.g. moving from a state of rest), i.e., to accelerate. Force can also be described intuitively as a ...
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 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 Science (BA). The current Chi ...
.
Definition
The dyne is defined as "the force required to accelerate a
mass
Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different ele ...
of one
gram
The gram (originally gramme; SI unit symbol g) is a unit of mass in the International System of Units (SI) equal to one one thousandth of a kilogram.
Originally defined as of 1795 as "the absolute weight of a volume of pure water equal to th ...
at a rate of one
centimetre
330px, Different lengths as in respect to the Electromagnetic spectrum, measured by the Metre and its deriveds scales. The Microwave are in-between 1 meter to 1 millimeter.
A centimetre (international spelling) or centimeter (American spellin ...
per
second
The second (symbol: s) is the unit of time in the International System of Units (SI), historically defined as of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds ea ...
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
The metre–tonne–second or MTS system of units is a system of physical units. It was invented in France, hence the unit names ''sthène'' and ''pièze'', and became its legal system between 1919 and 1961 ("décret" 5 May 1961, "Journal Officie ...
.
: 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 is what allows objects with a higher density than water such as razor blades and insects (e.g. water striders) t ...
. 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 (abbreviated 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 ...
*
Erg
The erg is a unit of energy equal to 10−7joules (100 nJ). It originated in the Centimetre–gram–second system of units (CGS). It has the symbol ''erg''. The erg is not an SI unit. Its name is derived from (), a Greek word meaning 'work' o ...
References
{{CGS units
Centimetre–gram–second system of units