One horsepower is equal to 550 of these units per second
These two units of power are related to each other by a simple conversion... [DOC] [TLE] SI Metirc System of Units [PAR] Systems of units for measuring these were developed from the very beginning of 
..... as equal to 550 foot-pounds per second and 1 mechanical horsepower (hp)... [DOC] [TLE] What is Power?