Power work donetime requiredP FdtPFv550Energy, Work, and PowerPOWERRev. 0Page 9CP-05MechanicalPowerMechanical energy used per unit time is called mechanical power. Mechanical power is the rate atwhich work is done. Mechanical power is expressed in units of joules/sec (joules/s) or a watt (W)in the mks system, and feet - pounds force per second (ft-lbf/s) or horsepower (hp) in the Englishsystem. Mechanical power can be calculated using the following mathematical expression.Because work can be defined as force times distance, we can also use the following equation: (5-6)where:P=Power (W or ft-lbf/s)F=Force (N or lbf)d=distance (m or ft)t=time (sec)One horsepower is equivalent to 550 ft-lbf/s and 745.7 watts. Because in the equation above ddivided by tis the same as velocity, an alternate description of power is as follows.(5-7)where:P=power (hp)F=force (lbf)v=velocity (ft/s)When using equations 5-6 or 5-7, you must either assume force and velocity are constant or thataverage values of the force and velocity are used.

Integrated Publishing, Inc.

6230 Stone Rd, Unit QPort Richey, FL34668

Phone For Parts Inquiries: (727) 493-0744
Google +