# Physical Constants

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Description | Symbol | Formula | Value_{1} | Unit_{1} | Value_{2} | Unit_{2} |
---|---|---|---|---|---|---|

Absolute zero, temperature | 0 | ^{o}K | -273.15 | ^{o}C | ||

Acceleration of gravity at earth's surface | g | 9.81 | m/s^{2} | 32.2 | ft/s^{2} | |

Atmospheric pressure at sea level | 1.013 25 *10^{5} | N/m^{2} | 14.69 | lb/in^{2} | ||

Atomic mass unit | 1.660 540 *10^{-27} | kg | 1.000 | u | ||

Avogadro's constant | N_{A} | 6.022 141*10^{23} | mol^{-1} | |||

Base of natural logaritms | e | 2.718 281 828... | ||||

Base of natural logaritms | lnx | 2.3026 log x | ||||

Bohr magneton | μ_{B} | e h/4πm_{e} | 9.274 009 994 *10^{-24} | Am^{2} | 5.788 381 *10^{-5} | eV/T |

Bohr radius | a_{0} | ε_{0}h^{2}/π m_{e}e^{2} | 5.291 772 106 7* 10^{-11} | m | 2.08 *10^{-9} | in |

Boltzmann constant | k | R/N_{A} | 1.380 648 52 *10^{-23} | J/K | 8.617 330 *10^{-5} | eV/K |

Charge of electron | e | 1.602 176 *10^{-19} | C | |||

Faraday constant | F | e N_{A} | 9.6 485332 89 * 10^{4} | C/mol | 26.801 | Ah/mol |

Fine structure constant | α | 7.297 20* 10^{-3} | ||||

Gas constant (molar, ideal) | R | 8.314 459 8 | J/molK | 82.057 338 | cm^{3}atm/molK | |

Gravitational constant | G | 6.674 08 *10^{-11} | m^{3}/kg s^{2} | |||

Mass of electron (rest mass) | m_{e} | 9.109 383 56 *10^{-31} | kg | 5.485 799*10^{-4} | u | |

Mass of neutron | m_{n} | 1.674 927 47* 10^{-27} | kg | 1.008 664 915 | u | |

Mass of proton | m_{p} | 1.672 621 90 *10^{-27} | kg | 1.007 276 466 | u | |

Permeability of a vacuum | μ_{0} | 4p *10^{-7} | kg m/s^{2}A^{2} | |||

Permittivity of a vacuum | ε_{0} | 1/μ_{0 }c_{0}^{2} | 8.854 187 817 *10^{-12} | C^{2}/Nm^{2} | A^{2}s^{4}/kg m^{3} | |

Planck's constant | h | 6.626 070 040 * 10^{-34} | J s | 4.135 667 *10^{-15} | eV s | |

Radiation constant, first | C_{1} | 2 π h c^{2} | 3.741 844 *10^{-16} | Wm^{2} | ||

Radiation constant, second | C_{2} | h c/k | 1.438 833 *10^{-2} | mK | ||

Ratio of a circle's circumference(C) to its diameter | π | C/d | 3.141 592 653… | |||

Rydberg constant | R∞ | m_{e}e^{4}/8ε_{0}^{2}h^{3}c_{0} | 1.097 373 156 * 10^{7} | m^{-1} | ||

Speed of light in vacuum | c_{0} | 2.99 792 458 *10^{8} | m/s | |||

Stefan-Boltzmann constant | σ | 5.670 367*10^{-8} | W/m^{2}K^{4} | 11.7 *10^{-8} | cal/cm^{2}dayK^{4} | |

Volume ideal gas, 1 atm, 0°C | V_{m} | 22413.6 | cm^{3}/mol | 22.4136 | liter/mol | |

Volume ideal gas,1 atm, 25°C | V_{m} | 24466.1 | cm^{3}/mol | 1.0244651 | m^{3}/mol |

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