In terms, actual energy (TR:5) (LH:4) (TL:9) is William Rankine's 1853 term for what Thomas Young had previously referred to as "energy of vis viva" or "vis viva energy" (1807), and what William Thomson and Peter Tait would later call "kinetic energy" (1862), each generally meaning the energy of a body in motion, defined by the product of its mass and velocity.
The following are quotes:
- “Actual [energy], or sensible energy, is a measure, transmissible, and transformable condition, whose presence causes a substance to tend to change its state in one or more respects. By the occurrence of such changes actual energy disappears, and is replaced by potential [energy] or latent energy; which is measured by the product of a change of state into the resistance against which that change is made. The vis viva of matter in motion, thermometric heat, radiant heat, light, chemical action, and electric currents, are forms of actual energy; amongst those of potential energy are the mechanical powers of gravitation, elasticity, chemical affinity, statical electricity, and magnetism.”
- (a) Rankine, William. (1853). “On the General Law of the Transformation of Energy”, read before the Philosophical Society of Glasgow, Jan 5th; in Proceedings, 3(5). (b) Rankine, William. (1872). Miscellaneous Scientific Papers Volume One (§11: pgs. 203-08, 229). Griffin, 1881.
- Actual energy – Hmolpedia 2020.