The crane lifts a load weighing 3 tons evenly at a speed of 30 m / min. How much power does the crane engine generate?

m = 3 t = 3000 kg.
g = 10 m / s2.
V = 30 m / min = 0.5 m / s.
N -?
The power of the crane N is called a scalar physical quantity that shows how quickly it performs mechanical work A. The power of the crane Np is expressed by the formula: N = A / t, where t is the time of performing useful mechanical work.
We will assume that the lifting of the load by the crane is uniformly rectilinear.
In this case, mechanical work A will be determined by the formula: Ap = m * g * h, where m is the mass of the lifted load, g is the acceleration of gravity, h is the height of the load.
The net power of the crane Nп will be determined by the formula: N = m * g * h / t.
The ratio of the lifting height to the lifting time h / t is called the lifting speed V: h / t = V.
The formula for determining the power will take the form: N = m * g * V.
Answer: the crane motor has a power of N = 15 kW.