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internal energy JUST WRITTEN FOR YOU

/ɪnˈtɜrnəl ˈɛnədʒi/ · in.tur nal.en.er.gy
noun
  1. 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. The internal energy of a gas is directly related to its temperature and pressure.
Did you know? The concept of internal energy was first introduced by the German physicist Rudolf Clausius in 1850, who used it to describe the energy of a system that is not directly observable.
Written by Lexi Wordsworth, Dictionary Editor 0 lookups Added Jul 15, 2026