Constants/Conversions

Physics Constants

speed of light c = 2.997925 x 108 m/s

gravitation constant G = 6.67 x 10-11 N m2 /kg2 

Avagado's number NA = 6.022 x 1026 particles/kmol

Boltzmann's constant k = 1.3806 x 10-23 J/K

gas constant R = 8314 J/kmol K 

or R = 1.9872 kcal/kmol K 

Plank's constant h = 6.6262 x 10-34 J s 

electron charge e = 1.60219 x 10-19 C   

electron rest mass me = 9.1095 x 10-31 kg

or me = 5.4858 x 10-4 u  

proton rest mass mp = 1.67264 x 10-27 kg

or mp = 1.00728 u

neutron rest mass mn = 1.67492 x 10-27 kg  

or mn = 1.00866 u

permittivity constant ɛ0 =  8.85419 x 10-12 C2/N m2       

permeability constant µ0 = 4π x 10-7 N/A2      

gravitational acceleration g = 9.80665 m/sec2 or 32.17 ft/s2

mass of earth 5.98 x 1024 kg   

average radius earth 6.37 x 106 m

average density earth 5.57 g/m3

average earth/moon distance 3.84 x 108 m    

average earth/sun distance 1.496 x 1011 m

mass of sun 1.99 x 1030 kg   

radius of sun 7 x 108 m  

Sun's radiation intensity at earth 0.032 cal/cm2 s

or 0.134 J/cm2 s