To examine the process of heat transfer leading to the phase change –
||JAMES PRESCOTT JOULE
English physicist, who worked experimentally on linkage
between heat and other forms of energy. Joule discovered that
the power of the engine was proportional to the product of the
current and the emf. In 1840, he stated a law, now called
Joule's Law, that heat is produced in an electrical conductor.
Joule's detailed experiments proved that any form of energy,
whether electrical, chemical or mechanical produces an equal
amount of heat.
He showed that heat is produced by motion and established the
equivalence between amounts of heat and mechanical work. In
1843 he published his value for the amount of work required to
produce a unit of heat, called the mechanical equivalent of
heat. International unit of energy, the Joule, is named in his
honour. Joule' s experiments were fundamental in bringing the
formulation of the law of conservation of energy.