# Mathematical and other constants

This is a small collection of constants that might come in handy. These were collected in the days before Google. So it is possible to obtain more accurate numbers on line. But I rather like having them in one place. Besides, they work on my old sliderule just fine!

 Constant Abreviation Value Units Pi p 3.14159265 e e 2.71828183 Absolute zero (0 Kelvin) -273.160000 Celsius Acceleration due to Earth’s gravity a 9.81 metres/second² Avogadro’s number N 6.02E-023 molecules/mole Electronic charge e 1.60E-019 coulombs Electron, mass of m 9.11E-031 kg Electron, charge/mass ratio e/m 1.76E+011 coulombs/kg Electron, radius of r 2.19E-015 metres Faraday’s Constant F 66487 C/mole Gas Constant R 8.31E+000 j/K/mole Gravitational constant G 6.67E-011 Newtons metres²/kg Latent heat of evaporation of water 2.26E+006 joules/kg Latent heat of fusion of ice 333400 joules/kg Mechanical equivalent of heat 4.18 joules/calorie Plank’s constant h 6.63E-034 joules seconds Velocity of sound at STP 343.6 metres/second Velocity of light in vacuo c 299792500 metres/second Radius of Planet Earth 6378100 metres Geostationary Orbit 35786000 metres