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: | ||

m_{u} | = 1.66053873(13) x 10^{-27} kg | |

m_{u} | = 1.66053873 x 10^{-27} kg | |

Uncertainty in m_{u} | = 0.00000013 x 10^{-27} kg | |

Name | Symbol | Value |
---|---|---|

Atomic Mass Unit | m_{u} | 1.66053873(13) x 10^{-27} kg |

Avogadro's Number | N_{A} | 6.02214199(47) x 10^{23} mol^{-1} |

Bohr Magneton | _{B} | 9.27400899(37) x 10^{-24} J T^{-1} |

Bohr Radius | a_{o} | 0.5291772083(19) x 10^{-10} m |

Boltzmann's Constant | k | 1.3806503(24) x 10^{-23} J K^{-1} |

Compton Wavelength | _{c} | 2.426310215(18) x 10^{-12} m |

Deuteron Mass | m_{d} | 3.34358309(26) x 10^{-27} kg |

Electric Constant | _{o} | 8.854187817 x 10^{-12} F m^{-1} |

Electron Mass | m_{e} | 9.10938188(72) x 10^{-31} kg |

Electron-Volt | eV | 1.602176462(63) x 10^{-19} J |

Elementary Charge | e | 1.602176462(63) x 10^{-19} C |

Faraday Constant | F | 9.64853415(39) x 10^{4} C mol^{-1} |

Fine Structure Constant | 7.297352533(27) x 10^{-3} | |

Hartree Energy | E_{h} | 4.35974381(34) x 10^{-18} J |

Hydrogen Ground State | 13.6057 eV | |

Josephson Constant | K_{j} | 4.83597898(19) x 10^{14} Hz V^{-1} |

Magnetic Constant | _{o} | 4 x 10^{-7} |

Molar Gas Constant | R | 8.314472(15) J K^{-1} mol^{-1} |

Natural Unit of Action | 1.054571596(82) x 10^{-34} J s | |

Newtonian Constant of Gravitation | G | 6.673(10) x 10^{-11} m^{3} kg^{-1} s^{-2} |

Neutron Mass | m_{n} | 1.67492716(13) x 10^{-27} kg |

Nuclear Magneton | _{n} | 5.05078317(20) x 10^{-27} J T^{-1} |

Planck Constant | h | 6.62606876(52) x 10^{-34} J sh = 2 |

Planck Length | l_{p} | 1.6160(12) x 10^{-35} m |

Planck Mass | m_{p} | 2.1767(16) x 10^{-8} kg |

Planck Time | t_{p} | 5.3906(40) x 10^{-44} s |

Proton Mass | m_{P} | 1.67262158(13) x 10^{-27} kg |

Rydberg Constant | R_{H} | 10 9.73731568549(83) x 10^{5} m^{-1} |

Stefan Boltzmann Constant | 5.670400(40) x 10^{-8} W m^{-2} K^{-4} | |

Speed of Light in Vacuum | c | 2.99792458 x 10^{8} m s^{-1} |

Thompson Cross Section | _{e} | 0.665245854(15) x 10^{-28} m^{2} |

Wien Displacement Law Constant | b | 2.8977686(51) x 10^{-3} m K |

Source:

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

- NIST Fundamental Constants

AMAZING! - International System of Units

In-depth information on the SI, the modern metric system - Uncertainty of Measurement Results

Guidelines for the expression of uncertainty in measurement - eFunda - Online Reference for Engineers

eFunda provides extensive Unit Conversion, Equations, and Material Data of value to engineers.

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'The strength and weakness of physicists is that we believe in what we can measure. And if we can't measure it, then we say it probably doesn't exist. And that closes us off to an enormous amount of phenomena that we may not be able to measure because they only happened once. For example, the Big Bang. ... That's one reason why they scoffed at higher dimensions for so many years. Now we realize that there's no alternative... '**Michio Kaku**

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