The mass of an electron is 1/1836 of mass of proton. It is one of the fundamental constants of physics. Mass of an electron (me) = 9.109 *10-31 kilograms. Symbol of elementary charge is e. The electrical charge on an electron is equal to the charge on proton, but with opposite sign. The elementary charge, usually denoted by e or sometimes qe, is the electric charge carried by a single proton or, equivalently, the magnitude of the negative electric charge carried by a single electron, which has charge −1 e.[2] This elementary charge is a fundamental physical constant. This method is not how the most accurate values are measured today. Paul Dirac persuasively argued in 1931 that if magnetic monopoles exist, then electric charge must be quantized; however, it is unknown whether magnetic monopoles actually exist. National Institute of Standards and Technology, International Bureau of Weights and Measures, "Of the "Electron," or Atom of Electricity", "Three Surprising Facts About the Physics of Magnets", "CODATA Recommended Values of the Fundamental Physical Constants: 2006", "CODATA recommended values of the fundamental physical constants: 1998", Journal of Physical and Chemical Reference Data, https://en.wikipedia.org/w/index.php?title=Elementary_charge&oldid=964464558, Creative Commons Attribution-ShareAlike License, This page was last edited on 25 June 2020, at 17:15. Electron Charge and Mass Quantity Symbol Value Units Mass me 9.109 x 10-31 kg Charge e 1.602 x 10-19 C I. Time: 1 Planck Time = 5.39124x10-44 s = sqrt (h bar G/c 5) 1 Sidereal Day = 23 h 56 m 04.09054 s 1 Solar Day = 24 h = 86400 s 1 Sidereal Year = 3.155815x10 7 s 1 Tropical Year = 3.155693x10 7 s Energy: 1 Joule = 2.39x10-1 calorie 1 Joule = 10 7 ergs 1 eV = 1.602177x10-12 erg = … The mass of an electron is 1/1836 of mass of proton. [18], Another accurate method for measuring the elementary charge is by inferring it from measurements of two effects in quantum mechanics: The Josephson effect, voltage oscillations that arise in certain superconducting structures; and the quantum Hall effect, a quantum effect of electrons at low temperatures, strong magnetic fields, and confinement into two dimensions. Thus, an object's charge can be exactly 0 e, or exactly 1 e, −1 e, 2 e, etc., but not, say, 1/2 e, or −3.8 e, etc. Electric charge on an electron is -1.602 10-19 C (or experimental value -1.602176634 10-19 Coulombs). Experimental measurements of the elementary charge, In terms of the Avogadro constant and Faraday constant, From the Josephson and von Klitzing constants. However, the unit of energy electronvolt reminds us that the elementary charge was once called electron.