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Rest energy of the electron

  1. Dec 14, 2014 #1
    Electrons in a particle accelerator reach a speed of 0.999c relative to the laboratory. Is the rest energy of the electron equal to zero?
     
  2. jcsd
  3. Dec 14, 2014 #2

    Nugatory

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    The kinetic energy of an electron (or anything else, for that matter) at rest is zero.

    The total energy of the electron, calculated from ##E=\gamma{m_0}c^2## or ##E^2=(m_0c^2)^2+(pc)^2"##, is .511 511 MeV when the electron is at rest and greater when it is moving and the kinetic energy is non-zero.

    [Edit - left the decimal point out the first time around]
     
    Last edited: Dec 14, 2014
  4. Dec 14, 2014 #3

    jtbell

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    The rest energy of an electron is 0.511 MeV, regardless of how fast it is moving.
     
  5. Dec 14, 2014 #4

    Matterwave

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    .511MeV or 511keV bro, 511MeV is some ginormous electron.
     
  6. Dec 14, 2014 #5

    Nugatory

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    :)
     
  7. Dec 14, 2014 #6

    jtbell

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    It's overweight even for a muon. :oldruck:
     
  8. Dec 14, 2014 #7
    thanks..
     
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