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Physics - Constants

Much of the groundbreaking work in physics has allowed the results to take the form of constants. Certain values - like the speed of light for example - are relatively unchanged and can safely integrate themselves into new problems to be solved.

The list of constants given here are the ones used mostly by Astronomers. A complete list of physical constants is available from the Physics Laboratory of the National Institute of Standards and Technology.

In addition to constants, I have also integrated some useful quantities as well.

Name: Symbol: Value:
Astronomical Unit A.U. 1.496 x 1011 meters
Atomic Mass Constant mu 1.6605386x10-27 kg
Boltzmann Constant k 1.3806505x10-23 J K-1
Electron Volt eV 1.60217653x10-19 J
Gravitational Constant G 6.6742x10-11 m3 kg-1 s-2
Gravity Constant Over h-bar G/ħ c 6.7087x10-39 (GeV/c2)-2
Light Year ly 9.4605x1015 m
Mass of Proton mp 1.67262171x10-27 kg
Mass of Neutron mn 1.67492728x10-27 kg
Mass of Electron me 9.1093826x10-31 kg
Mass of Hydrogen Atom mH 1.6735x10-27 kg
Parsec pc 3.0857x1016 m
Planck Constant h 6.6260693x10-34 J s
Planck Constant over 2π ħ 1.05457168x10-34 J s
Rydberg Constant R 6.6x10-12
Solar Mass 1.989x1030 kg
Solar Radius 6.9599x108 m
Solar Luminosity 3.90x1026 W
Speed of Light c 299,792,458 m s-1
Standard Atmosphere   101,325 Pa
Stefan-Boltzmann Constant σ 5.670400x10-8 W m-2 K-4
Wien Displacement Law b 2.8977685x10-3 n K
Year - Earth   365.2564 days
Year - Earth   3.156x107 sec

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