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Fundamental Physical Constants

Values given below are from the CODATA 1998 recommended by the National Institute of Standards and Technology of United States (NIST).

Values contain the (uncertainty) in the last two decimal places given in brackets. Values that do not have this uncertainty listed are exact.

For example:
mu= 1.66053873(13) x 10-27 kg
mu= 1.66053873 x 10-27 kg
Uncertainty in mu

= 0.00000013 x 10-27 kg

Atomic Mass Unit mu1.66053873(13) x 10-27 kg
Avogadro's Number NA6.02214199(47) x 1023 mol-1
Bohr Magneton B9.27400899(37) x 10-24 J T-1
Bohr Radius ao0.5291772083(19) x 10-10 m
Boltzmann's Constant k1.3806503(24) x 10-23 J K-1
Compton Wavelength c 2.426310215(18) x 10-12 m
Deuteron Mass md 3.34358309(26) x 10-27 kg
Electric Constant o8.854187817 x 10-12 F m-1
Electron Mass me9.10938188(72) x 10-31 kg
Electron-Volt eV1.602176462(63) x 10-19 J
Elementary Charge e1.602176462(63) x 10-19 C
Faraday Constant F9.64853415(39) x 104 C mol-1
Fine Structure Constant 7.297352533(27) x 10-3
Hartree Energy Eh4.35974381(34) x 10-18 J
Hydrogen Ground State 13.6057 eV
Josephson ConstantKj4.83597898(19) x 1014 Hz V-1
Magnetic Constant o4 x 10-7
Molar Gas Constant R8.314472(15) J K-1 mol-1
Natural Unit of Action 1.054571596(82) x 10-34 J s
Newtonian Constant of Gravitation G6.673(10) x 10-11 m3 kg-1 s-2
Neutron Mass mn1.67492716(13) x 10-27 kg
Nuclear Magneton n5.05078317(20) x 10-27 J T-1
Planck Constant h6.62606876(52) x 10-34 J s
h = 2
Planck Length lp1.6160(12) x 10-35 m
Planck Mass mp2.1767(16) x 10-8 kg
Planck Time tp5.3906(40) x 10-44 s
Proton Mass mP1.67262158(13) x 10-27 kg
Rydberg Constant RH 10 9.73731568549(83) x 105 m-1
Stefan Boltzmann Constant 5.670400(40) x 10-8 W m-2 K-4
Speed of Light in Vacuum c2.99792458 x 108 m s-1
Thompson Cross Section e0.665245854(15) x 10-28 m2
Wien Displacement Law Constant b 2.8977686(51) x 10-3 m K


CODATA Recommended Values of the Fundamental Physical Constants: 1998
by Peter J. Mohr and Barry N. Taylor
National Institute of standards and Technology, Gaithersburg, MD 20899-8401

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