The crane lifts a load of 8.8 t to a height of 10 m for 50 seconds. Determine the amount of current consumed

The crane lifts a load of 8.8 t to a height of 10 m for 50 seconds. Determine the amount of current consumed by the crane, if the voltage is 220 V, and the efficiency. crane 80%.

Given: m (mass of the lifted load) = 8.8 t (in SI m = 8800 kg); h (lifting height) = 10 m; t (duration of crane operation) = 50 s; U (operating voltage) = 220 V; η (efficiency of the crane used) = 80% or 0.8.

Constants: g (acceleration due to gravity) ≈ 10 m / s2.

The current consumed by the used crane can be expressed from the formula: η = Nп / Nк = (A / t) / (U * I) = m * g * h / (U * I * t), whence I = m * g * h / (η * U * t).

Calculation: I = 8800 * 10 * 10 / (0.8 * 220 * 50) = 100 A.