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Related to coulombic: magnetic force, Coulomb potential

SI units

the units of measurement generally accepted for all scientific and technical uses; together they make up the International System of Units. (See also metric system.) The abbreviation SI, from the French Système International d'Unités, is used in all languages. There are seven base SI units, defined by specified physical measurements, and two supplementary units. Units are derived for any other physical quantities by multiplication and division of the base and supplementary units. The derived units with special names are shown in the accompanying table.

SI is a coherent system. This means that units are always combined without conversion factors. The derived unit of velocity is the meter per second (m/s); the derived unit of volume is the cubic meter (m3). If you know that pressure is force per unit area, then you know that the SI unit of pressure (the pascal) is the unit of force divided by the unit of area and is therefore equal to 1 newton per square meter.

The metric prefixes can be attached to any unit in order to make a unit of a more convenient size. The symbol for the prefix is attached to the symbol for the unit, e.g., nanometer (nm) = 10−9 m. The units of mass are specified in terms of the gram, e.g., microgram (μg) = 10−9 kg.

Only one prefix is used with a unit; the use of units such as the millimicrometer is no longer acceptable. When a unit is raised to a power, the power applies to the prefix as well, e.g., a cubic millimeter (mm3) = 10−9 m3. When a prefix is used with a ratio unit, it should be in the numerator rather than in the denominator, e.g., kilometers/second (km/s) rather than meters/millisecond (m/ms). Only prefixes denoting powers of 103 are normally used. Hecto-, deka-, deci-, and centi- are usually attached only to the metric system units gram, meter, and liter.

Owing to the force of tradition, one noncoherent unit, the liter, equal to 10−3 m3, or 1 dm3, is generally accepted for use with SI. The internationally accepted abbreviation for liter is the letter l; however, this can be confused with the numeral 1, especially in typescript. For this reason, the capital letter L is also used as a symbol for liter. The lower case letter is generally used with prefixes, e.g., dl, ml, fl. The symbols for all other SI units begin with a capital letter if the unit is named after a person and with a lower case letter otherwise. The name of a unit is never capitalized.


Charles A. de, French physicist, 1736-1806. See: coulomb.

cou·lomb (C, Q),

The unit of electrical charge, equal to 3 × 109 electrostatic units; the quantity of electricity delivered by a current of 1 A in 1 s equal to 1/96,485 faraday.
[CA de Coulomb, Fr. physicist, 1736-1806]


/cou·lomb/ (C) (koo´lom) the SI unit of electric charge, defined as the quantity of electric charge transferred across a surface by 1 ampere in 1 second.

coulomb (C)

Etymology: Charles A. de Coulomb, French physicist, 1736-1806
the SI unit of electricity equal to the quantity of charge transferred in 1 second across a conductor in which there is a constant current of 1 ampere, or 1 ampere-second.


(C) (kū'lom)
The SI unit of electrical charge, equal to 3 × 109 electrostatic units; the quantity of electricity delivered by a current of 1 ampere in 1 sec; equal to 1/96,485 faraday; also used to measure radiation.
See also: roentgen
[CA de Coulomb, Fr. physicist, 1736-1806]


1. the unit of electrical charge, defined as the quantity of electrical charge transferred by 1 ampere in 1 second. Symbol C.
2. the SI unit of exposure to radiation. 1 coulomb per kilogram = 3876 roentgen; abbreviated C/kg.
References in periodicals archive ?
In this research study, an attempt has been made to evaluate CED behavior of the prepared coating binders (modified epoxidized cardanol-formaldehyde novolacs, MECNs) in terms of electrodeposition characteristics, such as electrodeposition yield (ED yield), coulombic yield (CY), and dry film thickness (DFT).
We know that the best energy coefficients of the semi-empirical mass formula [12-14] are, Coulombic energy coefficient [E.
The combination of the decreased viscous force and the Coulombic force at high temperatures determines the pressure capacity.
A lot of people in the battery industry have realized the importance of the coulombic efficiency measurement, but they've always been limited by the testing equipment.
This concentration of electrons exerts a Coulombic attraction on the positive nuclei of the two atoms and this gives rise to a covalent bond.
We carry out Monte Carlo simulations using long-range repulsive electrostatic interactions including both the screened Coulombic and dipole-dipole contributions.
Coulombic interactions between the ions themselves are known to cause systematic shifts in the observed cyclotron frequency, otherwise known as space-charge effects.
A strong coulombic interaction between the zinc and the carboxylate anions leads to tight ion pairs that tend to associate into ionomer-like interactions.
E3 Cells have performance-lives that are 4 to 5 times longer than lead-acid batteries, which means they can be charged and discharged a larger number of times without general failure or significant loss of performance; -- E3 Cells have high coulombic efficiencies, which means that more of the accumulated charge is available for use during discharge cycles; and -- E3 Cells can withstand significantly faster sustained charge and discharge rates, which means that the stored energy is available more quickly;
These droplets have high charge density and coulombic forces cause them to split into successively smaller units until individual charged molecules are released.
Electron backscatter is primarily the result of the electrostatic interaction of incident electrons with the Coulombic field of the atom (essentially the positive charge of the nucleus), which in turn is produced by the total charge of the protons (partially modified by the screening effect of the inner orbital electrons), which is related to the number of each, that is Z.
For larger distances, the standard coulombic repulsive term is included.