The crane lifts a slab with a volume of 1 m3 to a height of 2 m in 50 seconds. What work did the crane do

The crane lifts a slab with a volume of 1 m3 to a height of 2 m in 50 seconds. What work did the crane do if the density of the slab is 2000 kg / m3? Determine the power of the crane if its efficiency is 50%.

t = 10 s.

P = 1000 N.

h = 5 m.

N -?

The power of the crane N is called a scalar physical quantity that shows the speed of performing mechanical work. We express the power of the crane N by the formula: N = A / t, where A is the mechanical work performed by it, t is the time of mechanical work.

We will assume that the crane lifts the load evenly in a straight line. In this case, the mechanical work A performed by him will be determined by the formula: A = P * h, where P is the weight of the lifted load, h is the lifting height.

Crane power N will be determined by the formula: N = P * h / t.

N = 1000 N * 5 m / 10 s = 500 W.

Answer: while lifting the load, the crane develops a power of N = 500 W.