Meaning of Joule's law

Joule's' law'

Pronunciation: [key]
— Physics. Physics.
  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.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.