An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A unit of → energy in the → International System of Units equal to the → work performed by one → newton over a distance of 1 → meter. 1 J is equivalent to 10⁷ ergs = 1 Watt second = 2.78 × 10^-7 kWh = 0.2389 calories = 6.24 × 10¹⁸ eV.

In honor of the English physicist James Prescott Joule (1818-1889), who established that the various forms of energy (mechanical, electrical, and heat) are basically the same and can be changed, one into another.

Joule is in Pers. pronounced as žul, loaned from the Fr. rendering of the E. name.

A → conductor becomes heated by the passage of an electric current through it due to the → resistance of the conductor. Same as → Ohmic dissipation.

→ joule; → effect.

The proportional relationship of mechanical energy to thermal energy, equal to 4.184 joules per calorie. Also called mechanical equivalent of heat.

→ joule; → constant.

The change in the temperature of a gas in the → throttling process.

→ Joule; → Thomson; → effect.