When lifting the beam by 5 meters, the work of 5000 J was performed to find the mass of the beam.

Data: Δh – change in the height of the specified beam (Δh = 5 m); A – work perfect when lifting the beam (A = 5000 J).

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

To find out the mass of the specified beam, consider the formula: A = ΔEp = mx * g * Δh, from where we express: mx = A / (g * Δh).

Let’s calculate: mx = A / (g * Δh) = 5000 / (10 * 5) = 100 kg.

Answer: The specified beam, according to the calculation, has a mass of 100 kg.