electron volt n.
Abbr. eV, ev
A unit of energy equal to the energy acquired by an electron falling through a potential difference of one volt, approximately 1.602 × 10-19 joule.
A unit used to measure the energy of subatomic particles. One electron volt is defined as the energy needed to move an electron (which has an electric charge equal to -1) across an electric potential of one volt.
unit of energy commonly used in atomic and nuclear physics, equal to the energy gained by an electron (a charged particle carrying unit electronic charge when the electrical potential at the electron increases by one volt). The electron volt equals 1.602 10-12 erg. The abbreviation MeV indicates 106 (1,000,000) electron volts and GeV, 109 (1,000,000,000).
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