Physical Constants

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	N_A		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	μ_B	e h/4πm_e	9.274009994×10^-24	Am²	5.788381×10^-5	eV/T
Bohr radius	a₀	ε₀h²/π m_ee²	5.2917721067×10^-11	m	2.08×10^-9	in
Boltzmann constant	k	R/N_A	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 N_A	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)	m_e		9.10938356×10^-31	kg	5.485799×10^-4	u
Mass of neutron	m_n		1.67492747×10^-27	kg	1.008664915	u
Mass of proton	m_p		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/μ₀c₀²	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∞	m_ee⁴/8ε₀²h³c₀	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	V_m		22413.6	cm³/mol	22.4136	liter/mol
Volume ideal gas,1 atm, 25°C	V_m		24466.1	cm³/mol	1.0244651	m³/mol

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Physical Constants