Centimeter-Gram-Second System

(redirected from cgs)
Also found in: Dictionary, Thesaurus, Medical, Acronyms, Wikipedia.

centimeter-gram-second system

[¦sent·ə‚mēd·ər ¦gram ′sek·ənd ‚sis·təm]
An absolute system of metric units in which the centimeter, gram mass, and the second are the basic units. Abbreviated cgs system.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Centimeter-Gram-Second System


(cgs system), the system of units of physical quantities that is based on the three fundamental units of the centimeter for length, the gram for mass, and the second for time.

In 1861 the British Association for the Advancement of Science appointed a committee on electrical standards, whose membership included such leading physicists of the day as W. Thomson (Lord Kelvin), J. Maxwell, and C. Wheatstone. The committee proposed that a system of units based on fundamental units of length, mass, and time be adopted for mechanics and electrodynamics. Ten years later, the association formed a new committee, which made a final choice of the centimeter, gram, and second as the fundamental units. The First International Congress of Electricians, which was held in Paris in 1881, also adopted the cgs system. Since then, the system has been widely used in scientific research. Since the introduction of the International System of Units (SI), the use of cgs units has been permitted alongside SI units in physics and astronomy.

With respect to mechanical measurements, the most important derived units in the cgs system are as follows: speed, cm/sec; acceleration, cm/sec2; force, dyne (dyn); pressure, dyn/cm2; work and energy, erg; power, erg/sec; dynamic viscosity, poise (P); and kinematic viscosity, stokes (St).

For electrodynamics, two cgs systems—the cgs electromagnetic system and the cgs electrostatic system—were originally adopted. The electromagnetic system is based on Coulomb’s law of the force between two point magnetic poles, and the electrostatic system on Coulomb’s law of the force between two point electric charges. In the cgs electromagnetic system, the permeability of empty space μ0 is dimensionless and is taken as 1. The permittivity of empty space ɛ0 = 1/c2 sec2/cm2, where c = (2.99792458 ± 0.000000012) X 1010 is the numerical value of the speed of light in cm/sec. The cgs electromagnetic system includes the following units: magnetic flux, maxwell (Mx); magnetic flux density, gauss (G); magnetic field strength, oersted (Oe); and magnetomotive force, gilbert (Gb). Special names have not been adopted for the electrical units in this system.

In the cgs electrostatic system, ɛ0 = 1, and μ0 = 1/c2 sec2/cm2. The electrical units of this system have not been given special names. Their sizes are in general inconvenient for measurements, and they are used primarily in theoretical work.

Elements of the electromagnetic and electrostatic cgs systems are mixed in the Gaussian system, which has become the most widely used system in the second half of the 20th century. In this system, μ0 = 1, and ɛ0 = 1. The magnetic units of this

Table 1. Relations between the most important cgs units and the corresponding SI units1
QuantitySI systemcgs electromagnetic systemcgs electrostatic systemGaussian system
1In table, c is the numerical value of the speed of light in cm/sec
Force.....................1 N10-5N10-5N10-5N
Work, energy ................1 J10-7J10-7J10-7J
Dynamic viscosity .............1 N.sec/m20.1 N.sec/m20.1 N.sec/m20.1 N.sec/m2
Kinematic viscosity ............1 m2/sec10-4m2/sec10-4 m2/sec10-4m2/sec
Current....................1A10A10/c A10/c A
Electric charge..........1C10C10/cC10/cC
Electric potential..............1V10-8V10-8c Vl0-8c V
Electric resistance.............10-9 Ω10-9C2Ω10-9C2Ω
Electric capacitance ...........1F109Fl09/c2 Fl09/c2 F
Magnetic field strength ..........1 A/m103/(4π) A/m103/(4πc) A/m103/(4π) A/m
Magnetic flux density ...........1T10-4T10-4cT10-4 T
Magnetic flux ................1 Wb10-8 Wb10-8c Wb10-8 W

system are identical to those of the cgs electromagnetic system, and the electrical units are identical to those of the cgs electrostatic system.

Table 1 shows the relations between the most important units of the three cgs systems and the corresponding SI units.


Burdun, G. D. Spravochnik po Mezhdunarodnoi sisteme edinits. Moscow, 1971.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
2017), argues that there are areas for improvement in the performance evaluation of CGS in many cases.
The CGs of these children were screened and those who met the selection criteria were included in the study.
Exhibitors of CGS included: ECommPay, BetConstruct, Prospectacy, SB Betting Software, SBTech, Sunobel, UNIC Training and Development Unit.
Mills, CGS's senior vice president of global contact center solutions.
issued a memorandum to departments and divisions of the Provincial Government extending front line services to give full support to the CGS.
Research has shown that strained CGs for patients with cardiovascular (CVD) disease neglect their own healthy behaviors (Burton, Newsom, Schulz, Hirsch, & German, 1997) and have higher risk of mortality (Schulz & Beach, 1999).
BANKING AND CREDIT NEWS-January 10, 2014--Generational Equity client CGS Technologies acquired
In fact, Latinos hold a mere 37 out of 5,511 board seats in the Fortune 500, according to findings from the 2013 Corporate Governance Study (CGS).
The results of our previous study revealed the detectable blood levels of type III cryoglobulins (Cgs) in SCZ and found the presence of complement activation split products in these complexes [9].
CGS Publishing Technologies International released the latest version of the leading proofing software ORIS Color Tuner.
CGS, a leading global provider of technology solutions and services, today announced their contact center and BPO operations in Romania has received the second place award in the "Best International Call Center" category at the 2013 Call Center Excellence Awards.
First Motors, the dealers of Hyundai in Bahrain, in collaboration with CGS Al Sdi Refrigeration Air Conditioning (CGS Bahrain) is now providing customers with chiller and freezer transportation solutions.