Mechanical Constants

This list of mechanical constants represent the most common values used in engineering, physics, and chemistry.

If you know of others that should be added, please send me an e-mail.

Visit NIST for all constants, units, and uncertainties.
This is their Extensive Listing of constants.


NameSymbolValue
HorsepowerHP745.7  W
AtmosphereAtm14.70  lb/in2
PiP3.141 592 653 589 793 238 46
Natural log basee2.718 281 828 459 045 235 36
Square root of 2√21.414 213 562 372 095 048 80
Euler's constantg0.577 215 664 901 532 860 61
Golden Ratiof1.618 033 988 749 894 848 20
1º of latitude at 40º latitude 69  mi
Acceleration of gravityg32.1726  ft/s2
Knotkt1.1508  mi/hr
Speed of sound @ 0ºC 1087.1  ft/s
Water heat of fusion @ 0ºC∆Hfus79.71  cal/g
Water heat of vaporization @ 0ºC∆Hvap539.55  cal/g
Acre 43 560  ft2