Mechanical Constants

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

Visit NIST for all constants, units, and uncertainties.

This is their Extensive Listing of constants.

Name Symbol Value
Horsepower HP 745.7  W
Atmosphere Atm 14.70  lb/in2
Pi P 3.141 592 653 589 793 238 46
Natural log base e 2.718 281 828 459 045 235 36
Square root of 2 √2 1.414 213 562 372 095 048 80
Euler's constant g 0.577 215 664 901 532 860 61
Golden Ratio f 1.618 033 988 749 894 848 20
1º of latitude at 40º latitude   69  mi
Acceleration of gravity g 32.1726  ft/s2
Knot kt 1.1508  mi/hr
Speed of sound @ 0ºC   1087.1  ft/s
Water heat of fusion @ 0ºC ∆Hfus 79.71  cal/g
Water heat of vaporization @ 0ºC ∆Hvap 539.55  cal/g
Acre   43 560  ft2