The crane lifts a body weighing 0.8 t at a speed of 0.2. What work will the crane do in 20 seconds?

Given: m (mass of the lifted body) = 0.8 t (in SI m = 800 kg); V (body lifting speed) = 0.2 m / s; t (duration of the crane operation) = 20 s.

Constants: according to the condition g (gravitational acceleration) = 10 m / s2.

The work that the crane under consideration will perform in 20 s is determined by the formula: A = N * t = F * V * t = m * g * V * t.

Let’s calculate: A = 800 * 10 * 0.2 * 20 = 32 * 10 ^ 3 J (32 kJ).

Answer: The crane in question will perform work of 32 kJ.