see also Units and Conversions

SymbolValueDescription
q1.602 × 10-19 coulomb electronic charge
m09.108 × 10-31 kg electron rest mass
c2.998 × 108 m/s speed of light in vacuum
ε08.85418 × 10-14 farad/cm
8.85418 × 10-12 farad/m
permitivity of free space
h6.626 × 10-27 erg·s
6.626 × 10-34 joule·s
Planck's constant
k1.380 × 10-16 erg/K
1.380 × 10-23 joule/K
Boltzmann's constant
σ5.67 × 10-8 J/m2s K4 Stefan-Boltzmann constant
kT/q0.02586 Vthermal voltage at 300 K
λ0 wavelength of 1eV photon1.24 µm