Task data: t (duration of the crane motor) = 40 s; m (mass of the lifted load) = 3 t (in SI m = 3 * 10 ^ 3 kg); h (lifting height) = 30 m.
Reference values: g (acceleration due to gravity) ≈ 10 m / s2.
The engine power of the crane used is determined by the formula: N = A / t = m * g * h / t.
Let’s make a calculation: N = 3 * 10 ^ 3 * 10 * 30/40 = 22.5 * 10 ^ 3 W (22.5 kW).
Answer: The motor of the crane used has a power of 22.5 kW.
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