Joule's law

Joule's law
1. the principle that the rate of production of heat by a constant direct current is directly proportional to the resistance of the circuit and to the square of the current.
2. the principle that the internal energy of a given mass of an ideal gas is solely a function of its temperature.
[1850-55; named after J. P. JOULE]

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      in electricity, mathematical description of the rate at which resistance in a circuit converts electric energy into heat energy. The English physicist James Prescott Joule (Joule, James Prescott) discovered in 1840 that the amount of heat per second that develops in a wire carrying a current is proportional to the electrical resistance of the wire and the square of the current. He determined that the heat evolved per second is equivalent to the electric power absorbed, or the power loss.

      A quantitative form of Joule's law is that the heat evolved per second, or the electric power loss, P, equals the current I squared times the resistance R, or P = I2R. The power P has units of watts, or joules per second, when the current is expressed in amperes and the resistance in ohms.

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Universalium. 2010.

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Look at other dictionaries:

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  • joule's law — noun Usage: usually capitalized J Etymology: after J. P. Joule : either of two statements in physics: (1) the rate at which heat is produced by a steady current in any part of an electric circuit is jointly proportional to the resistance and the… …   Useful english dictionary

  • Joule’s law — Džaulio dėsnis statusas T sritis Standartizacija ir metrologija apibrėžtis Dėsnis, formuluojamas taip: laidininke, kai juo teka elektros srovė, išsiskiriantis šilumos kiekis Q yra proporcingas srovės kvadratui I², laidininko varžai R ir srovės… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

  • Joule's law — /ˈdʒulz lɔ / (say joohlz law) noun 1. the principle that internal energy of a given mass of an ideal gas is independent of its volume or pressure and depends only on its temperature. 2. the principle that the heat produced by an electric current… …  

  • Joule's law — noun Physics a law stating that the heat produced by an electric current i flowing through a resistance R for a time t is proportional to i2Rt …   English new terms dictionary

  • Joule's law — noun the quantitative relationship between the quantity of heat produced in a conductor and the electric current flowing through it …   Wiktionary

  • Joule's Law —   The rate of heat production by a steady current in any part of an electrical circuit that is proportional to the resistance and to the square of the current, or, the internal energy of an ideal gas depends only on its temperature.   U.S. Dept.… …   Energy terms

  • Joule's laws — are a pair of laws concerning the heat produced by a current and the energy dependence of an ideal gas to that of pressure, volume, and temperature, respectively. Joule s first law, also known as the Joule effect, is a physical law expressing the …   Wikipedia

  • Joule'o dėsnis — statusas T sritis automatika atitikmenys: angl. Joule s law vok. Joulesches Gesetz, n rus. закон Джоуля Ленца, m pranc. loi de Joule, f ryšiai: sinonimas – Džaulio dėsnis …   Automatikos terminų žodynas

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