HP, Torque, Units

[adt1]

>:By definition:
>:Horsepower = (rpm * Torque) / 5252
>:
>:Thus, at 5252 RPM, HP = 5252*Torque/5252 = Torque

>Please don't stop now., the bulbs are going off....  What are the units
>used to get the 5252 number?


 torque * rotational speed = power

 1 Btu = 778.17 ft-lbf
 1 min = 60 sec
 1 hp = 0.70678 Btu/sec
 1 rev = 2*pi rad


 T [ft-lbf] * N [rev/min] * [1 Btu/778.17 ft-lbf] * 
 
   [1 min/60 sec] * [1 hp/{0.70678 Btu/sec}] * [2*pi rad/rev] = 

 T*N/5252 = P [hp]