1 Lifting a weight to a height of 20 m takes 20 s for one crane and 10 s for another

Computer Science Jan 28, 2021

1 Lifting a weight to a height of 20 m takes 20 s for one crane and 10 s for another. Is there any difference in the amount of work done on the weight by each crane?

2. A construction crane lifts a prestressed concrete beam weighing 3 short tons from the ground to the top of piers that are 36 ft above the ground. Determine theamount of work done considering (a) the beam and (b) the crane as the system. Express your answers in both lbf·ft and Btu.