Atomic01 - University of Cape Town

PHY322S Atomic Physics .
Natural units: the factor c
To evaluate an expression in natural units where [ = c = 1], put in
factors and c to get known groupings, eg mc 2 , then finally replace c
factors with
c = (2π) −1 (6.6 × 10 −34 )(1.6 × 10 −19 ) −1 (3 × 10 8 )(10 9 ) eV nm
= 197 eV nm
= 197 MeV fm
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