Rest energy of the electron - calculation discrepancy

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SUMMARY

The calculation of the rest energy of an electron using the formula E=mc² yields a value of 0.512 MeV when using a mass of 9.109 x 10-31 kg and the speed of light as 2.9979 x 108 m/s. The accepted value is 0.511 MeV, indicating a discrepancy due to an incorrect conversion factor. The correct conversion factor is 1.602 x 10-19 joules per eV, not 1.6 x 10-19 joules. This highlights the importance of precise constants in calculations.

PREREQUISITES
  • Understanding of Einstein's mass-energy equivalence (E=mc²)
  • Familiarity with the concept of electron rest mass (9.109 x 10-31 kg)
  • Knowledge of the speed of light in a vacuum (2.9979 x 108 m/s)
  • Proficiency in unit conversion, specifically between Joules and electronvolts (eV)
NEXT STEPS
  • Research the implications of using precise constants in physics calculations
  • Learn about the significance of the electron rest mass in particle physics
  • Study the conversion factors between Joules and MeV for various particles
  • Explore common errors in energy calculations in quantum mechanics
USEFUL FOR

Physicists, students studying particle physics, and anyone involved in calculations related to energy and mass in quantum mechanics will benefit from this discussion.

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When I use E=mc2 to calc. the rest energy of an electron, I get .512Mev not .511Mev. I am using 9.109x10-31 kg for the rest mass of an electron and 2.9979x10^8 m/s for the speed of light in a vacuum.
Can anyone tell me why there ís a discrepancy between my results and the accepted answer?
 
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What are you using as the conversion factor between Joules and Mev?
 
You found my mistake. I was using 1.6x10-19joules equals 1 eV, instead of 1.602x10-19.
Thank you for your help.
 

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