énergie

Traductions

• anglais

  Date : 1987

  Définition

  The fundamental active entity of the universe.
  
  A physical entity which is present in a system in different forms, transformable one into the other, of which the most important examples are: mechanical, electromagnetic, chemical, thermal, radiant.

  Note :

  Among its more important manifestations are (1) electromagnetic radiation (photons, or radiant energy); (2) the energy of combustion (thermal energy); (3) electrical energy; (4) kinetic energy (the energy of motion); (5) nuclear energy, the binding force that holds protons and neutrons together in the atomic nucleus; and (6) free energy, a thermodynamic function describing the energy available to substance for reaction with other substances. The three laws of thermodynamics state the energy conditions which determine the nature and extent of chemical reactions. The first and best-known of these (conservation of energy) is that the total of energy in the universe is constant and cannot be increased or diminished. Einstein was the first to formulate the concept of the equivalence of energy and mass, expressed by the equation E = mc², from which has developed the science of nuclear phenomena.

  Terme :

  1. energy