Table of Constants

Fundamental constants from NIST Physics Lab

Name	Symbol	Value	Units	Relative Uncertainty
Speed of light (in vacuum)	${\displaystyle c}$	${\displaystyle 299\ 792\ 458}$	${\displaystyle \mathrm {m} \ \mathrm {s} ^{-1}}$	(exact)
Magnetic constant	${\displaystyle \mu _{0}}$	${\displaystyle 4\pi \times 10^{-7}\approx }$	${\displaystyle \mathrm {N} \ \mathrm {A} ^{-2}}$	(exact)
Electric constant	${\displaystyle \epsilon _{0}}$	${\displaystyle 1/(\mu _{0}c^{2})\approx }$	${\displaystyle \mathrm {F} \ \mathrm {m} ^{-1}}$	(exact)
Newtonian gravitational constant	${\displaystyle G}$	${\displaystyle 6.674\ 2(10)\times 10^{-11}}$	${\displaystyle \mathrm {m} ^{3}\ \mathrm {kg} ^{-1}\ \mathrm {s} ^{-2}}$	${\displaystyle 1.5\times 10^{-4}}$
Plank's constant	${\displaystyle h}$	${\displaystyle 6.626\ 069\ 3(11)\times 10^{-34}}$	${\displaystyle \mathrm {J} \ \mathrm {s} }$	${\displaystyle 1.7\times 10^{-7}}$
Elementary charge	${\displaystyle e}$	${\displaystyle 1.602\ 176\ 53(14)\times 10^{-19}}$	${\displaystyle \mathrm {C} }$	${\displaystyle 8.5\times 10^{-8}}$
Mass of the electron	${\displaystyle m_{e}}$	${\displaystyle 9.109\ 382\ 6(16)\times 10^{-31}}$	${\displaystyle \mathrm {kg} }$	${\displaystyle 1.7\times 10^{-7}}$
Mass of the proton	${\displaystyle m_{p}}$	${\displaystyle 1.672\ 621\ 71(29)\times 10^{-27}}$	${\displaystyle \mathrm {kg} }$	${\displaystyle 1.7\times 10^{-7}}$
Mass of a neutron	${\displaystyle m_{n}}$
Fine structure constant	${\displaystyle \alpha =e^{2}/(2\epsilon _{0}hc)}$	${\displaystyle 7.297\ 352\ 568(24)\times 10^{-3}}$	dimentionless	${\displaystyle 3.3\times 10^{-9}}$
Molar gass constant	${\displaystyle R}$	${\displaystyle 8.314\ 472(15)}$	${\displaystyle \mathrm {J} \ \mathrm {mol} ^{-1}\ \mathrm {K} ^{-1}}$	${\displaystyle 1.7\times 10^{-6}}$
Boltzmann's constant	${\displaystyle k}$	${\displaystyle 1.380\ 650\ 5(24)}$	${\displaystyle \mathrm {J} \ \mathrm {K} ^{-1}}$	${\displaystyle 1.8\times 10^{-6}}$
Avogadro's number	${\displaystyle N_{A}}$	${\displaystyle 6.022\ 141\ 5(10)\times 10^{23}}$	${\displaystyle \mathrm {mol} ^{-1}}$	${\displaystyle 1.7\times 10^{-7}}$
Rydberg constant	${\displaystyle R_{\infty }}$	${\displaystyle 10\ 973\ 731.568\ 525(73)}$	${\displaystyle \mathrm {m} ^{-1}}$	${\displaystyle 6.6\times 10^{-12}}$
Atmosphere	${\displaystyle \mathrm {atm} }$	${\displaystyle 101325}$		(exact)
Electronvolt	${\displaystyle \mathrm {eV} }$	${\displaystyle 1.60\times 10^{-19}}$
Bohr radius	${\displaystyle a_{0}}$	${\displaystyle 5.292\times 10^{-11}}$
Coulomb's constant	${\displaystyle k}$	${\displaystyle {\frac {1}{4\pi \epsilon _{0}}}\approx }$
Faraday constant	${\displaystyle F}$	${\displaystyle e\times N_{A}\approx }$
Gravitational acceleration on Earth	${\displaystyle g}$
Mass of the Earth
Mass of the Moon
Mean radius of the Earth
Mean radius of the Moon
Dirac's Constant	${\displaystyle \hbar }$
Speed of sound in air at STP
Unified Atomic Mass Unit	${\displaystyle u}$
Vacuum Permittivity	${\displaystyle \epsilon _{0}}$

• 1 Atmosphere Pressure (1 atm) : 1.0 × 10⁵ N/m² = 1.0 × 10⁵ Pa
• 1 Electron Volt (1 eV) : 1.60 × 10⁻¹⁹ J
• Bohr radius (a₀)  : 5.292 × 10⁻¹¹ m
• Coulomb's Law Constant (k) : 1/(4 π ε₀) = 9.0 × 10⁹ N·m²/C²
• Faraday constant (F)  : 96,485 C·mol⁻¹
• Gravitational accelaration (g) : 9.80665 m·s^-2
• Mass of a neutron (m_n) : 1.67495 × 10⁻²⁷ kg
• Mass of Earth : 5.98 × 10²⁴ kg
• Mass of the Moon : 7.35 × 10²² kg
• Mean radius of Earth : 6.37 × 10⁶ m
• Mean radius of the Moon : 1.74 × 10⁶ m
• Dirac's Constant (${\displaystyle \hbar }$) : ${\displaystyle h/(2\pi )}$ = 1.05457148 × 10⁻³⁴ J·s
• Speed of sound in air at STP : 3.31 × 10² m/s
• Unified Atomic Mass Unit (u) : 1.66 × 10⁻²⁷ kg
• Vacuum Permittivity (ε₀) : 8.85 × 10⁻¹² C²/(N·m²)

Item	Proton	Neutron	Electron
Mass	1	1	Negligible
Charge	+1	0	-1
Spin	${\displaystyle {\frac {1}{2}}}$	${\displaystyle {\frac {1}{2}}}$	${\displaystyle {\frac {1}{2}}}$

See Also