# Coulomb force

Coulomb force

also called  Coulomb Interaction,

attraction or repulsion of particles or objects because of their electric charge. One of the basic physical forces, the electric force is named for a French physicist, Charles-Augustin de Coulomb (Coulomb, Charles-Augustin de), who in 1785 published the results of an experimental investigation into the correct quantitative description of this force.

Two like electric charges, both positive or both negative, repel each other along a straight line between their centres. Two unlike charges, one positive, one negative, attract each other along a straight line joining their centres. The electric force is operative between charges down to distances of at least 10-16 metre, or approximately one-tenth of the diameter of atomic nuclei. Because of their positive charge, protons within nuclei repel each other, but nuclei hold together because of another basic physical force, the strong interaction, or nuclear force (strong force), which is stronger than the electric force. Massive, but electrically neutral, astronomical bodies such as planets and stars are bound together in solar systems and galaxies by still another basic physical force, gravitation, which though much weaker than the electric force, is always attractive and is the dominant force at great distances. At distances between these extremes, including the distances of everyday life, the only significant physical force is the electric force in its many varieties along with the related magnetic force.

The magnitude of the electric force F is directly proportional to the amount of one electric charge, q1, multiplied by the other, q2, and inversely proportional to the square of the distance r between their centres. Expressed in the form of an equation, this relation, called Coulomb's law, may be written by including the proportionality factor k as F = kq1q2/r2. In the centimetre–gram–second system of units, the proportionality factor k in a vacuum is set equal to 1 and unit electric charge is defined by Coulomb's law. If an electric force of one unit (one dyne) arises between two equal electric charges one centimetre apart in a vacuum, the amount of each charge is one electrostatic unit, esu, or statcoulomb. In the metre–kilogram–second and the SI systems, the unit of force (newton), the unit of charge (coulomb), and the unit of distance (metre), are all defined independently of Coulomb's law, so the proportionality factor k is constrained to take a value consistent with these definitions, namely, k in a vacuum equals 8.98 × 109 newton square metre per square coulomb. This choice of value for k permits the practical electrical units, such as ampere and volt, to be included with the common metric mechanical units, such as metre and kilogram, in the same system.

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Universalium. 2010.

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• Coulomb force — Kulono jėga statusas T sritis Standartizacija ir metrologija apibrėžtis Dviejų viena kitos atžvilgiu nejudančių elektringųjų dalelių (kūnų) sąveikos jėga: stūmos, jei krūviai q₁ ir q₂ vienarūšiai, traukos, jei – įvairiarūšiai. Išreiškiama Kulono… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

• Coulomb force — Kulono jėga statusas T sritis fizika atitikmenys: angl. Coulomb force vok. Coulomb Kraft, f; Coulombsche Kraft, f rus. кулонова сила, f; кулоновская сила, f pranc. force coulombienne, f …   Fizikos terminų žodynas

• coulomb force — /ˈkulɒm fɔs/ (say koohlom faws) noun the force between two electrically charged bodies. If the charges are of the same polarity, either positive or negative, the force is repulsive (coulomb repulsion); if they are of opposite polarity the force… …   Australian-English dictionary

• Coulomb force — noun the electrostatic force between two charges, as described by Coulombs law …   Wiktionary

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• Coulomb, Charles-Augustin de — born June 14, 1736, Angoulême, France died Aug. 23, 1806, Paris French physicist. After serving as a military engineer in the West Indies, he returned to France in the 1780s to pursue scientific research. To investigate Joseph Priestley s law of… …   Universalium

• force de Coulomb — Kulono jėga statusas T sritis Standartizacija ir metrologija apibrėžtis Dviejų viena kitos atžvilgiu nejudančių elektringųjų dalelių (kūnų) sąveikos jėga: stūmos, jei krūviai q₁ ir q₂ vienarūšiai, traukos, jei – įvairiarūšiai. Išreiškiama Kulono… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

• Coulomb-Kraft — Kulono jėga statusas T sritis Standartizacija ir metrologija apibrėžtis Dviejų viena kitos atžvilgiu nejudančių elektringųjų dalelių (kūnų) sąveikos jėga: stūmos, jei krūviai q₁ ir q₂ vienarūšiai, traukos, jei – įvairiarūšiai. Išreiškiama Kulono… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas