## Wikipedia - طاقة (ar) energy, $$E$$

https://doi.org/10.1351/goldbook.E02101
In mechanics the sum of @[email protected] and @[email protected] In thermodynamics the @[email protected] or @[email protected] increase, $$\Delta U$$, is the sum of @[email protected] and @[email protected] brought to the system. Only changes in energy are measurable. For photons $E=h\ \nu$where $$h$$ is the @[email protected] and $$\nu$$ the frequency of radiation. In relativistic physics $E=m\ c^{2}$ where $$c$$ is the speed of light and $$m$$ the mass.
Source:
Green Book, 2nd ed., p. 12 [Terms] [Book]