Appendix 8: Some Important Physical Constants

Speed of light c = 2.9979 × 108 m/s
Gravitational constant G = 6.673 × 10−11 N m2/kg2
Planck’s constant h = 6.6261 × 10−34 J s
    = 4.1357 × 10−15 eV s
Boltzmann constant k = 1.3807 × 10−23 J/K
    = 8.6173 × 10−5 eV/K
Stefan-Boltzmann constant σ = 5.6704 × 10−8 W m−2 K−4
Mass of electron me = 9.1094 × 10−31 kg
Mass of proton mp = 1.6726 × 10−27 kg
Mass of neutron mn = 1.6749 × 10−27 kg
Mass of hydrogen atom mH = 1.6735 × 10−27 kg
Rydberg constant R = 1.0973 × 107 m−1
Electron volt 1 eV = 1.6022 × 10−19 J