Power

POWER IS DEFINED AS THE TIME RATE OF DOING WORK. The common unit of mechanical power is the horsepower (hp) which is the equivalent of 33,000 foot-pounds of work per minute. If in the above problem the 2000-pound weight is lifted 10 feet in 2 minutes, the power required would be:

                            weight x distance

Horsepower    =    time  x  33,000

                               

Horsepower   = 2000 x 10  =  20,000    

                          2 x 33,000     66,000       =  .3 hp