internal energy

Thermodynam.
a function of thermodynamic variables, as temperature, that represents the internal state of a system that is due to the energies of the molecular constituents of the system. The change in internal energy during a process is equal to the net heat entering the system minus the net work done by the system. Symbol: U
[1885-90]

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      in thermodynamics, the property or state function that defines the energy of a substance in the absence of effects due to capillarity and external electric, magnetic, and other fields. Like any other state function, the value of the energy depends upon the state of the substance and not upon the nature of the processes by which it attained that state. In accordance with the first law of thermodynamics, when a system undergoes a change of state as a result of a process in which only work is involved, the work is equal to the change in internal energy. The law also implies that if both heat and work are involved in the change of state of a system, then the change in internal energy is equal to the heat supplied to the system minus the work done by the system.

      Sometimes it is convenient to represent the internal energy as a sum of terms that can be interpreted as kinetic energy, potential energy, and chemical energy.

      Internal energy is an extensive property—that is, its magnitude depends on the amount of substance in a given state. Its value usually is calculated with reference to some standard state rather than being expressed in absolute terms.

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Universalium. 2010.

Look at other dictionaries:

  • internal energy —  Internal Energy  Внутренняя энергия системы   Сумма кинетической и потенциальной энергий (в том числе энергии электромагнитного поля) частиц, составляющих данную систему. Является функцией состояния термодинамической системы, существование… …   Толковый англо-русский словарь по нанотехнологии. - М.

  • Internal energy — In thermodynamics, the internal energy of a thermodynamic system, or a body with well defined boundaries, denoted by U , or sometimes E , is the total of the kinetic energy due to the motion of molecules (translational, rotational, vibrational)… …   Wikipedia

  • internal energy — a measure of the internal energy stored within a material per unit volume. For most heat transfer problems, this energy consists just of thermal energy. The amount of thermal energy stored in a body is manifested by its temperature …   Mechanics glossary

  • internal energy — vidinė energija statusas T sritis Standartizacija ir metrologija apibrėžtis Sistemą sudarančių molekulių, atomų, laisvųjų elektronų ir kitokių mikrodalelių kinetinė energija ir dalelių sąveikos potencinė energija. atitikmenys: angl. inner energy; …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

  • internal energy — vidinė energija statusas T sritis chemija apibrėžtis Sistemą sudarančių molekulių, atomų, laisvųjų elektronų ir kitų mikrodalelių kinetinė energija ir dalelių sąveikos potencinė energija. atitikmenys: angl. inner energy; internal energy;… …   Chemijos terminų aiškinamasis žodynas

  • internal energy — vidinė energija statusas T sritis fizika atitikmenys: angl. inner energy; internal energy; intrinsic energy vok. innere Energie, f rus. внутренняя энергия, f pranc. énergie interne, f …   Fizikos terminų žodynas

  • internal energy — vidinė energija statusas T sritis Energetika apibrėžtis Vidinę energiją sudaro dujų molekulių slenkamojo ir sukamojo judesio energija, atomų svyravimo energija, molekulių sąveikos energija, t.y. vidinės energijos dedamosios yra medžiagos vidinė… …   Aiškinamasis šiluminės ir branduolinės technikos terminų žodynas

  • internal energy — noun : the total amount of kinetic and potential energy possessed by the molecules of a body and their ultimate parts owing to their relative positions and their motions inside the body and excluding the energy due to the passage of waves through …   Useful english dictionary

  • internal energy — /ɪnˌtɜnəl ˈɛnədʒi/ (say in.ternuhl enuhjee) noun the total energy stored within a physical system, consisting of the sum total of the kinetic and potential energies of its constituent particles …   Australian English dictionary

  • internal energy — noun a property, characteristic of the state of a thermodynamic system, the change of which is equal to the heat absorbed minus the work done by the system …   Wiktionary

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