Constants
This page lists various constants used in physics and some useful conversions.
Physical constants
The number in brackets represents the uncertainty in the constant, so that Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 6.626070040(81) \times 10^{-34}} has an uncertainty of Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 0.00000000081 \times 10^{-34}} .
| Name | Symbol | Value | Meaning | Used in | Exact |
|---|---|---|---|---|---|
| Planck's constant | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle h} | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 6.626070040(81) \times 10^{-34} \,} J s | It relates the frequency of a photon to its energy | Quantum mechanics | Inexact[1] |
| Speed of light | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle c} | 299,792,458 m s-1 | This is the speed of light in a vacuum | Most of physics, such as optics and relativity | Exact[2] |
| Permittivity of free space | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \epsilon_0} | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 8.854187817... \times 10^{-12}} F m-1 | Related to the strength of an electric field produced by a charge | Electromagnetism | Exact[3] |
| Permeability of free space | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mu_0} | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 4 \pi \times 10^{-7}} | Related to the strength of [[magnetic field]s produced by a current | Electromagnetism | Exact[4] |
| Elementary charge | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle e} | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 1.6021766208(98) \times 10^{-19}} C | The magnitude of the electric charge on an electron | Determines the strength of electric and magnetic fields produced by protons, electrons etc | Inexact[5] |
| Avogadro's number | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle N_A} | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 6.022140857(74) \times 10^{23}} mol-1 | The number of constituents in 1 mole of something | Chemistry, statistical mechanics, thermodynamics | Inexact[6] |
| Ideal gas constant | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle R} | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 8.3144598(48)} J mol-1 K-1 | Relates the pressure, volume, temperature and number of moles of an ideal gas | Thermodynamics | Inexact[7] |
Useful Conversions
1 atm = 101.1 kPa
1.000 calorie = 4.184 Joules
1 Calorie = 1000 calories
760 torr = 1 atm
760 mm Hg = 1 atm
Atomic mass unit: 1.00 amu = 1.67 x Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 10^{-27}} kg
Standard Temperature and Pressure (STP): temperature = 273 K and pressure = 1.00 atm
| Mass | Charge | |
|---|---|---|
| Proton | 1.67 x Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 10^-27 } kg | +1 |
| Neutron | 1.67 x Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 10^-27 } kg | 0 |
| Electron | 9.11 x Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 10^-31 } kg | -1 |
References
- ↑ http://physics.nist.gov/cgi-bin/cuu/Value?h
- ↑ http://physics.nist.gov/cgi-bin/cuu/Value?c
- ↑ http://physics.nist.gov/cgi-bin/cuu/Value?ep0
- ↑ http://physics.nist.gov/cgi-bin/cuu/Value?mu0
- ↑ http://physics.nist.gov/cgi-bin/cuu/Value?e
- ↑ http://physics.nist.gov/cgi-bin/cuu/Value?na
- ↑ http://physics.nist.gov/cgi-bin/cuu/Value?r