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abstraction > mathematical concept > unit > energy unit

energy unit
subject			fact

energy unit	is a unit of energy
	has definition (1) The capacity to do work. (2) Manifestation of a particular variety of force.
	is a kind of unit
unit	has historical origin
	represents

Kinds of energy unit :

• electron volt (10 facts) (eV, eV) - Unit employed to indicate the energy of a charged particle in terms of the energy received by the charge on an electron due to a potential difference of one volt. An approximate value (1 in 10⁴) for the energy of electromagnetic radiation expressed in electron volts is given by 1234 / λ, where λ is the wavelength in nanometres. In recent years it has become customary to write MeV and GeV for mega (10⁶) and giga (10⁹) electron volts. In the USA 10⁹ electron volts are often written as BeV, the letter B being used in this case as an abbreviation for the American billion (10⁹), but in 1948 the International Union of Pure and Applied Physics disapproved of the use of BeV and expressed a preference for GeV or 10⁹ eV. The electron volt was called the equivalent volt when it was originally introduced in 1912., Unit of energy used in atomic and nuclear physics; the kinetic energy acquired by one electron in passing through a potential difference of 1 volt in vacuum. Sometimes used as a unit of mass (see rest-mass energy)
• erg (9 facts) (dyne cm) - Unit of energy; the work done by a force of 1 dyne acting over a distance of 1 cm.
• joule (17 facts) (J) - Unit of work which is equal to a force of one newton acting over a distance of one metre in the direction of the force. It was recognized by the IEC in 1889. The specific heat of water at 15 °C is 4185.5 joule (kg °C)^-1, a figure previously always associated with J, the mechanical equivalent of heat., Unit of energy, work, or quantity of heat. 1 J is equal to a force of 1 newton acting over a distance of 1 meter. 1 J = 10⁷ ergs.
• rydberg (2 facts) - Unit of energy (R = h bar³c / me⁴) equal to 13.5978 eV (the ionization potential of hydrogen). Rydberg correction has definition