Physics 1 · Reference

Units and constants

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The college version

Quantity	Unit	Symbol	Equivalent
Force	newton	N	kg·m/s²
Energy, work, heat	joule	J	N·m
Power	watt	W	J/s
Pressure	pascal	Pa	N/m²
Electric charge	coulomb	C	A·s
Voltage, potential	volt	V	J/C
Resistance	ohm	Ω	V/A
Capacitance	farad	F	C/V
Magnetic field	tesla	T	N/(A·m)
Magnetic flux	weber	Wb	T·m²
Inductance	henry	H	V·s/A
Frequency	hertz	Hz	s⁻¹

Constant	Symbol	Value	Notes
Speed of light in vacuum	c	2.998 × 10⁸ m/s	Exact defined value: 299,792,458 m/s
Elementary charge	e	1.602 × 10^-19 C	Approximate
Gravitational acceleration (Earth surface)	g	9.80 m/s²	Approximate; varies slightly with location
Gravitational constant	G	6.674 × 10^-11 N·m²/kg²	Experimentally determined
Coulomb's constant	k	8.988 × 10⁹ N·m²/C²	k = 1/(4πε₀)
Permittivity of free space	ε₀	8.854 × 10^-12 C²/(N·m²)	Exact defined
Permeability of free space	μ₀	4π × 10^-7 T·m/A	Exact defined
Planck's constant	h	6.626 × 10^-34 J·s	Experimentally determined
Boltzmann constant	k_B	1.381 × 10^-23 J/K	Approximate
Universal gas constant	R	8.314 J/(mol·K)	R = N_A k_B
Avogadro's number	N_A	6.022 × 10²³ mol^-1	Approximate
Electron mass	m_e	9.109 × 10^-31 kg	Approximate
Proton mass	m_p	1.673 × 10^-27 kg	Approximate
Standard atmospheric pressure	P_atm	1.013 × 10⁵ Pa	At sea level

[ T_K = T_C + 273.15 ] [ T_F = \frac{9}{5}T_C + 32 ]

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