How high can a 2 kg load be lifted in 5 minutes using a 3 kW motor?

m = 2 kg.

g = 10 N / kg.

t = 5 min = 300 s.

N = 3 kW = 3000 W.

h -?

Engine power N is a physical quantity that shows how quickly the engine performs mechanical work. Let us express the engine power N by the formula: N = A / t.

Let’s assume that the engine lifts the load vertically and at a constant speed, that is, evenly.

We express the work of the engine A by the formula: A = m * g * h, where m is the mass of the load that is being lifted, g is the acceleration of gravity, h is the height of the body.

The formula for determining the engine power will take the form: N = m * g * h / t.

The lifting height h will be determined by the formula: h = N * t / m * g.

h = 3000 W * 300 s / 2 kg * 10 N / kg = 45000 m = 45 km.

Answer: the engine can lift the load to a height of h = 45 km.