With the help of a stationary block, the load is lifted to a height of 13 m.When lifting, a work of 20.7 kJ is performed.

With the help of a stationary block, the load is lifted to a height of 13 m.When lifting, a work of 20.7 kJ is performed. The efficiency of a simple mechanism is 94.2%. What is the mass of the load being lifted?

Initial data: h (height to which the load is lifted) = 13 m; A (work performed when lifting a load) = 20.7 kJ (20.7 * 10 ^ 3 J); η (efficiency of a simple mechanism (fixed block)) = 94.2% (0.942).
Reference values: g (acceleration due to gravity) ≈ 10 m / s2.
We express the mass of the lifted load from the formula: η = ΔEp / A = m * g * h / A, whence m = η * A / (g * h).
Calculation: m = 0.942 * 20.7 * 10 ^ 3 / (10 * 13) ≈ 150 kg.
Answer: The mass of the load being lifted is 150 kg.