Physical Constants (original) (raw)
Physical constants - SI Units.
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Physical Constants
| Description | Symbol | Formula | Value1 | Unit1 | Value2 | Unit2 |
|---|---|---|---|---|---|---|
| Absolute zero, temperature | 0 | K | -273.15 | oC | ||
| Acceleration of gravity at earth's surface | g | 9.81 | m/s2 | 32.2 | ft/s2 | |
| Atmospheric pressure at sea level | 1.01325×105 | N/m2 | 14.69 | lb/in2 | ||
| Atomic mass unit | 1.660540×10-27 | kg | 1.000 | u | ||
| Avogadro's constant | NA | 6.022141×1023 | mol-1 | |||
| Base of natural logaritms | e | 2.718 281 828... | ||||
| Base of natural logaritms | lnx | 2.3026 log(x) | ||||
| Bohr magneton | μB | e h/4πme | 9.274009994×10-24 | Am2 | 5.788381×10-5 | eV/T |
| Bohr radius | a0 | ε0h2/π mee2 | 5.2917721067×10-11 | m | 2.08×10-9 | in |
| Boltzmann constant | k | R/NA | 1.38064852×10-23 | J/K | 8.617330×10-5 | eV/K |
| Charge of electron | e | 1.602176×10-19 | C | |||
| Faraday constant | F | e NA | 9.648533289×104 | C/mol | 26.801 | Ah/mol |
| Fine structure constant | α | 7.29720×10-3 | ||||
| Gas constant (molar, ideal) | R | 8.3144598 | J/molK | 82.057338 | cm3atm/molK | |
| Gravitational constant | G | 6.67408×10-11 | m3/kg s2 | |||
| Mass of electron (rest mass) | me | 9.10938356×10-31 | kg | 5.485799×10-4 | u | |
| Mass of neutron | mn | 1.67492747×10-27 | kg | 1.008664915 | u | |
| Mass of proton | mp | 1.67262190×10-27 | kg | 1.007276466 | u | |
| Permeability of a vacuum | μ0 | 4p×10-7 | kg m/s2A2 | |||
| Permittivity of a vacuum | ε0 | 1/μ0 c02 | 8.854187817×10-12 | C2/Nm2 | A2s4/kg m3 | |
| Planck's constant | h | 6.626070040×10-34 | J s | 4.135667×10-15 | eV s | |
| Radiation constant, first | C1 | 2 π h c2 | 3.741844×10-16 | Wm2 | ||
| Radiation constant, second | C2 | h c/k | 1.438833×10-2 | mK | ||
| Ratio of a circle's circumference(C) to its diameter | π | C/d | 3.141592653… | |||
| Rydberg constant | R∞ | mee4/8ε02h3c0 | 1.097373156×107 | m-1 | ||
| Speed of light in vacuum | c0 | 2.99792458×108 | m/s | |||
| Stefan-Boltzmann constant | σ | 5.670367×10-8 | W/m2K4 | 11.7×10-8 | cal/cm2dayK4 | |
| Volume ideal gas, 1 atm, 0°C | Vm | 22413.6 | cm3/mol | 22.4136 | liter/mol | |
| Volume ideal gas,1 atm, 25°C | Vm | 24466.1 | cm3/mol | 1.0244651 | m3/mol |
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