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# Fundamental Physical Constants

 Quantity Symbol Value Unit speed of light in vacuum c; c0 299792458 m/s acceleration due to gravity g 9.80665 m/s2 Planck constant h 6.6260687652 x 10-34 J.s Avogadro constant NA; L 6.0221419947 x 1023 mol-1 atomic mass constant mu = 1/12 m(12C) = 1 u mu 1.6605387313 x 10-27 kg energy equivalent muc2 1.4924177812 x 10-10 J Faraday constant F 96485.341539 C/mol molar Planck constant NAh 3.99031268930 x 10-10 J.s/mol NAhc 0.1196265649291 J.m/mol molar gas constant R 8.314472 J/(mol.K) Boltzmann constant k 1.380650324 x 10-23 J/K molar volume of ideal gas RT/p Vm T = 273.15 K; p = 101.325 kPa 22.41399639 x 10-3 m3/mol T = 273.15 K; p = 100 kPa 22.71098140 x 10-3 m3/mol Loschmidt constant n0 2.686777547 x 1025 m-3 Sackur-Tetrode constant (absolute entropy constant) S0/R T1 = 1 K; p0 = 101.325 kPa - 1.164867844 T1 = 1 K; p0 = 100 kPa - 1.151704844 Stefan-Boltzmann constant σ 5.67040040 x 10-8 W/(m2.K4) first radiation constant c1 3.7417710729 x 10-16 W.m2 second radiation constant c2 1.438775225 x 10-2 m.K