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internal energy

American  

noun

Thermodynamics.
  1. 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. U


internal energy British  

noun

  1.  U.   E.  the thermodynamic property of a system that changes by an amount equal to the work done on the system when it suffers an adiabatic change. It is the sum of the kinetic and potential energies of its constituent atoms, molecules, etc

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of internal energy

First recorded in 1885–90

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Example Sentences

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To study these structural changes, it is important to determine the quantum states, internal energy, spin, and parity of the state.

From Science Daily

To avoid using a battery, they incorporate internal energy storage that can include a series of capacitors.

From Science Daily

"At present, electrical energy is mainly obtained by external energy, such as wind energy, hydroelectric energy, solar energy, and others. This work opens up the possibility of generating electrical energy through the molecular thermal motion of liquids, from the internal energy of the physical system that is essentially different from ordinary mechanical motion."

From Science Daily

The researchers think that the animals' use of internal energy, or active transport, when moving the salts could be the explanation.

From Science Daily

A metal that could produce its own internal energy at first seemed like a violation of the laws of physics.

From Salon