# energy equivalents

as mass -- E = m c 2
Planck mass: = 2.176 71 × 10 -8 kg
proton mass: m p = 1.672 623 1 × 10 -27 kg
electron mass: m e = 9.109 389 7 × 10 -31 kg

as frequency and wavelength -- E = h v = h c / λ
Planck length: = 1.616 05 × 10 -35 m
Compton wavelength: h / m e c = 2.426 310 58 × 10 -12 m

as temperature -- E = k T

 speed of light c = 299 792 458  m s -1 (exact) Planck's constant h = 6.626 075 5 × 10 -34 J s Boltzmann constant k = 1.380 658 × 10 -23 J K -1 gravitational constant G = 6.672 6 × 10 -11 N m 2 kg -2 electron charge e = 1.602 177 3 × 10 -19 C

Energy mass freq wavelength temp
Joules eV kg m e m p Planck Hz m K
Planck mass 1.96×10 9 1.22×10 28 2.18×10 -8 2.39×10 22 1.30×10 19 1 2.95×10 42 1.02×10 -34 * 1.42×10 32
1 GeV 1.60×10 -10 10 9 1.78×10 -27 1957 1.07 2.42×10 23 1.24×10 -15 1.16×10 13
m p 1.50×10 -10 0.938 × 10 9 1.67×10 -27 1836 1 1.09×10 13
10 13 K 1.38×10 -10 0.862×10 9 1.54×10 -27 1686 0.918 2.08×10 23 1.43×10 -15 10 13
1 MeV 1.60×10 -13 10 6 1.78×10 -30 1.957 1.07×10 -3 2.42×10 20 1.24×10 -12 1.16×10 10
10 10 K 1.38×10 -13 0.862×10 6 1.54×10 -30 1.686 9.18×10 -4 2.08×10 20 1.43×10 -12 10 10
m e 8.19×10 -14 0.511×10 6 9.11×10 -31 1 5.45 × 10 -4 2.43×10 -12 5.93×10 9
Rydberg 2.18×10 -18 13.6 3.29×10 15
1 eV 1.60×10 -19 1 1.78×10 -36 1.96×10 -6 1.07×10 -9 2.42×10 14 1.24×10 -6 1.16×10 4
10 4 K 1.38×10 -19 0.862 1.54×10 -36 1.69×10 -6 9.18×10 -10 2.08×10 14 1.43×10 -6 10 4
2.7 K 3.73×10 -23 2.33×10 -4 4.15×10 -40 4.55×10 -10 2.48×10 -13 5.63×10 10 0.0388 2.7
1 K 1.38×10 -23 8.62×10 -5 1.54×10 -40 1.69×10 -10 9.18×10 -14 2.08×10 10 0.0143 1
22 cm 9.03×10 -25 5.64×10 -6 1.36×10 9 0.22 0.07

* This is 2π larger than the "Planck length" itself, because of the use of in the latter's definition