Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

Horsepower, abbreviated as HP, is a measure of power or the rate of doing work. It is typically used to describe the work of an engine or machine and is the equivalent of moving 33,000 pounds through the distance of one foot in one minute.

Horsepower Formula

\(\large{ HP = \frac{ \tau \; s }{ 5252 }   }\)


\(\large{ HP }\) = horsepower

\(\large{ s }\) = speed (rpm)

\(\large{ \tau }\)  (Greek symbol tau) = torque

Solve for:

\(\large{ s = \frac{ 5252\; HP }{ \tau } }\)

\(\large{ \tau = \frac{ 5252\; HP }{ s }   }\)

horsepower conversion table

Horsepower Conversion Table
MultiplyByTo get
  2545.45766 BTU per hour, BTU/hr
  42.42429433 BTU per minute, BTU/min
  0.707071572 BTU per second, BTU/sec
  1980796.979 foot pound-force per hour
  33013.28298 foot pound-force per minute
  550.221383 foot pound-force per second
  1 horsepower, hp
  17702.8489 pound square foot per cubic second
  0.212121472 ton of refrigeration, ton
  2.6856E+13 dyne centimeter per hour
  4.476E+11 dyne centimeter per minute
  7460000000 dyne centimeter per second
  2685600 joule per hour
  44760 joule per minute
  746 joule per second
  746 watt, W
  0.746 kilowatt, kW
  0.000746 megawatt, MW
  0.000000746 gigawatt, GW
  2685600 newton meter per hour
  44760 newton meter per minute
  746 newton meter per second

Tags: Equations for Power Equations for Horsepower