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electronvolt
electronvolt (symbol eV) A unit of energy used in atomic and nuclear physics. It is defined as the energy acquired by an electron in falling through a potential difference of one volt. One electronvolt is equal to 1.602 × 10-19 joule. Electronvolts are used as a measure of the energy of cosmic rays and high-energy photons. X-rays and gamma rays can have energies of 100 000 eV or more. By comparison, optical photons have energies of 2–3 eV. The rest mass of atomic particles can also be expressed in terms of electronvolts, since mass and energy are equivalent. Hence the rest mass of an electron is about 500 keV and that of protons and neutrons about 1000 MeV. Electronvolts can be converted to wavelength (λ) by the formula λ = 1239.8nm/eV.
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"electronvolt." A Dictionary of Astronomy. 1997. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "electronvolt." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O80-electronvolt.html "electronvolt." A Dictionary of Astronomy. 1997. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-electronvolt.html |
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electron-volt
electron-volt abbr. eV, unit of energy used in atomic and nuclear physics; 1 electron-volt is the energy transferred in moving a unit charge , positive or negative and equal to that charge on the electron, through a potential difference of 1 volt. The maximum energy of a particle accelerator is usually expressed in multiples of the electron-volt, such as million electron-volts (MeV) or billion electron-volts (GeV). Because mass is a form of energy (see relativity ), the masses of elementary particles are sometimes expressed in electron-volts; e.g., the mass of the electron, the lightest particle with measurable rest mass, is 0.51 MeV/ c2 , where c is the speed of light. |
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"electron-volt." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "electron-volt." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1E1-electrn-v.html "electron-volt." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-electrn-v.html |
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electron volt
e·lec·tron volt (abbr.: eV) • n. Physics a unit of energy equal to the work done on an electron in accelerating it through a potential difference of one volt. |
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Cite this article
"electron volt." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "electron volt." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O999-electronvolt.html "electron volt." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-electronvolt.html |
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electronvolt
electronvolt (i-lek-tron-vohlt) n. a unit of energy equal to the increase in the energy of an electron when it passes through a rise in potential of one volt. Symbol: eV.
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"electronvolt." A Dictionary of Nursing. 2008. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "electronvolt." A Dictionary of Nursing. 2008. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O62-electronvolt.html "electronvolt." A Dictionary of Nursing. 2008. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-electronvolt.html |
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