# Table Of Physical Constants

NameSymbolValueUnit
Number \pi$$\pi3.14159265358979323846 Number ee2.71828182845904523536 Euler’s constant\gamma$$\begin{aligned} \gamma &= \lim\limits_{n\rightarrow\infty}\left(\sum\limits_{k=1}^n 1/k-\ln(n)\right) \\ &= 0.5772156649 \end{aligned}
Elementary charge$e$$1.60217733\cdot10^{-19}C Gravitational constantG,\kappa$$6.67259\cdot10^{-11}$m$^3$kg$^{-1}$s$^{-2}$
Fine-structure constant$\alpha=\frac{e^{2}}{2hc\epsilon_0}$$\approx \frac{1}{137} Speed of light in vacuumc$$2.99792458\cdot10^8$m/s (def)
Permittivity of the vacuum$\varepsilon_0$$8.854187\cdot10^{-12}F/m Permeability of the vacuum\mu_0$$4\pi\cdot10^{-7}$H/m
$(4\pi\varepsilon_0)^{-1}$$8.9876\cdot10^9Nm^2C^{-2} Planck’s constanth$$6.6260755\cdot10^{-34}$Js
Dirac’s constant$\hbar=\frac{h}{2\pi}$$1.0545727\cdot10^{-34}Js Bohr magneton\mu_{\rm B}=\frac{e\hbar}{2m_{\rm e}}$$9.2741\cdot10^{-24}$Am$^2$
Bohr radius$a_0$$0.52918 Rydberg’s constantRy13.595eV Electron Compton wavelength\lambda_{\rm Ce}=\frac{h}{m_{e} c}$$2.2463\cdot10^{-12}$m
Proton Compton wavelength$\lambda_{\rm Cp}=\frac{h}{m_{\rm p}c}$$1.3214\cdot10^{-15}m Reduced mass of the H-atom\mu_{\rm H}$$9.1045755\cdot10^{-31}$kg
Stefan-Boltzmann’s constant$\sigma$$5.67032\cdot10^{-8}Wm^{-2}K^{-4} Wien’s constantk_{\rm W}$$2.8978\cdot10^{-3}$mK
Molar gas constant$R$8.31441J$\cdot$mol$^{-1}\cdot$K$^{-1}$
Avogadro’s constant$N_{A}$$6.0221367\cdot10^{23}mol^{-1} Boltzmann’s constantk=\frac{R}{N_{A}}$$1.380658\cdot10^{-23}$J/K
Electron mass$m_{\rm e}$$9.1093897\cdot10^{-31}kg Proton massm_{\rm p}$$1.6726231\cdot10^{-27}$kg
Neutron mass$m_{\rm n}$$1.674954\cdot10^{-27}kg Elementary mass unitm_{u}=\frac{1}{12}m(^{12}_{6}C)$$1.6605656\cdot10^{-27}$kg
Nuclear magneton$\mu_{\rm N}$$5.0508\cdot10^{-27}J/T Diameter of the SunD_\odot$$1392\cdot10^6$m
Mass of the Sun$M_\odot$$1.989\cdot10^{30}kg Rotational period of the SunT_\odot25.38days Radius of EarthR_{\rm A}$$6.378\cdot10^6$m
Mass of Earth$M_{\rm A}$$5.976\cdot10^{24}kg Rotational period of EarthT_{\rm A}23.96hours Earth orbital periodTropical year365.24219879days Astronomical unitAU1.4959787066\cdot10^{11}m Light yearlj9.4605\cdot10^{15}m Parsecpc3.0857\cdot10^{16}m Hubble constantH$$\approx(75\pm25)$km$\cdot$s$^{-1}\cdot$Mpc$^{-1}$

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