Table Of Physical Constants

Key idea: Reference table of commonly used physical constants, symbols, values, and units.

University Physics Year 1

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Learning objectives

Use vector and differential or integral calculus to express physical change and accumulation.
Use complex numbers, linear algebra, and differential equations to solve coupled physical models.
Choose an efficient mathematical method and validate the result physically.

Scope and Status

This is an archived quick-reference table kept for legacy links. Some values or conventions may differ from newer standards and syllabus sheets.

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Name	Symbol	Value	Unit
Number π	π	3.14159265358979323846
Number e	e	2.71828182845904523536
Euler’s constant	γ	γ = lim _(n → ∞)(∑ₖ₌₁ⁿ 1/k- ln(n)); = 0.5772156649
Elementary charge	e	1.60217733 · 10⁻¹⁹	C
Gravitational constant	G,κ	6.67259 · 10⁻¹¹	m³kg⁻¹s⁻²
Fine-structure constant	α = e²/2hcε₀	≈ 1/137
Speed of light in vacuum	c	2.99792458 · 10⁸	m/s (def)
Permittivity of the vacuum	ε₀	8.854187 · 10⁻¹²	F/m
Permeability of the vacuum	μ₀	4π · 10⁻⁷	H/m
(4πε₀)⁻¹		8.9876 · 10⁹	Nm²C⁻²
Planck’s constant	h	6.6260755 · 10⁻³⁴	Js
Dirac’s constant	ħ = h/2π	1.0545727 · 10⁻³⁴	Js
Bohr magneton	μ_B = eħ/2mₑ	9.2741 · 10⁻²⁴	Am²
Bohr radius	a₀	0.52918	Å
Rydberg’s constant	Ry	13.595	eV
Electron Compton wavelength	λ_Ce = h/(mₑ c)	2.2463 · 10⁻¹²	m
Proton Compton wavelength	λ_Cp = h/mₚc	1.3214 · 10⁻¹⁵	m
Reduced mass of the H-atom	μ_H	9.1045755 · 10⁻³¹	kg
Stefan-Boltzmann’s constant	σ	5.67032 · 10⁻⁸	Wm⁻²K⁻⁴
Wien’s constant	k_W	2.8978 · 10⁻³	mK
Molar gas constant	R	8.31441	J·mol⁻¹ ·K⁻¹
Avogadro’s constant	N_A	6.0221367 · 10²³	mol⁻¹
Boltzmann’s constant	k = R/N_A	1.380658 · 10⁻²³	J/K
Electron mass	mₑ	9.1093897 · 10⁻³¹	kg
Proton mass	mₚ	1.6726231 · 10⁻²⁷	kg
Neutron mass	mₙ	1.674954 · 10⁻²⁷	kg
Elementary mass unit	mᵤ = (1/12)m(¹²₆C)	1.6605656 · 10⁻²⁷	kg
Nuclear magneton	μ_N	5.0508 · 10⁻²⁷	J/T
Diameter of the Sun	D_⊙	1392 · 10⁶	m
Mass of the Sun	M_⊙	1.989 · 10³⁰	kg
Rotational period of the Sun	T_⊙	25.38	days
Radius of Earth	R_A	6.378 · 10⁶	m
Mass of Earth	M_A	5.976 · 10²⁴	kg
Rotational period of Earth	T_A	23.96	hours
Earth orbital period	Tropical year	365.24219879	days
Astronomical unit	AU	1.4959787066 · 10¹¹	m
Light year	lj	9.4605 · 10¹⁵	m
Parsec	pc	3.0857 · 10¹⁶	m
Hubble constant	H	≈ (75±25)	km·s⁻¹ ·Mpc⁻¹

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Course and syllabus information

Course: University Physics Year 1
Edition: University Physics Year 1