constants

Collection of physical constants and conversion factors.

Physical constants

g

Earth standard gravity in \(\sf ms^{-1}\)

h

Planck constant in \(\sf Js\)

k

Boltzmann constant in \(\sf JK^{-1}\)

c

Speed of light in \(\sf ms^{-1}\)

N_A

Avogadro constant in \(\sf mol^{-1}\)

K, zero_celsius

Kelvin at 0 Celsius

triple_point_water

Triple point temperature of water \(\sf K\)

R

Universal gas constant in \(\sf J mol^{-1}K{^-1}\)

molar_mass_dry_air

Molar mass for dry air in \(\sf kg\,mol^{-1}\)

molar_mass_water

Molar mass for water vapor in \(\sf kg\,mol^{-1}\)

gas_constant_dry_air

Gas constant for dry air in \(\sf J K^{-1} kg^{-1}\)

gas_constant_water_vapor

Gas constant for water vapor in \(\sf J K^{-1} kg^{-1}\)

isobaric_mass_heat_capacity

Specific heat capacity in \(\sf J kg^{-1} K^{-1}\)

heat_of_vaporization

Heat of vaporization in \(\sf J kg{^-1}\)

Mathematical constants

golden

Golden ratio

SI prefixes

yotta

\(10^{24}\)

zetta

\(10^{21}\)

exa

\(10^{18}\)

peta

\(10^{15}\)

tera

\(10^{12}\)

giga

\(10^{9}\)

mega

\(10^{6}\)

kilo

\(10^{3}\)

hecto

\(10^{2}\)

deka

\(10^{1}\)

deci

\(10^{-1}\)

centi

\(10^{-2}\)

milli

\(10^{-3}\)

micro

\(10^{-6}\)

nano

\(10^{-9}\)

pico

\(10^{-12}\)

femto

\(10^{-15}\)

atto

\(10^{-18}\)

zepto

\(10^{-21}\)

Non-SI ratios

ppm

\(10^{-6}\) parts per million

ppb

\(10^{-9}\) parts per billion

ppt

\(10^{-12}\) parts per trillion

Binary prefixes

kibi, KiB

\(2^{10}\)

mebi, MiB

\(2^{20}\)

gibi

\(2^{30}\)

tebi

\(2^{40}\)

pebi

\(2^{50}\)

exbi

\(2^{60}\)

zebi

\(2^{70}\)

yobi

\(2^{80}\)

KB

\(10^3\)

MB

\(10^6\)

Earth characteristics

earth_mass

Earth mass in \(\sf kg\)

earth_radius

Earth radius in \(\sf m\)

atm

Standard atmosphere in \(\sf Pa\)