A balloon weighing 400 kg rose to a height of 1.5 km relative to the earth, its potential energy became equal.

To find out the potential energy acquired by the specified balloon, we apply the formula: Ek = mw * g * h.

Const: g – gravitational acceleration (since h «Rz (Earth’s radius), then assumed g ≈ 9.81 m / s2).

Data: mwsh – the mass of the specified balloon (mwsh = 400 kg); h – lifting height (h = 1.5 km; in SI h = 1.5 * 10 ^ 3 m).

Let’s perform the calculation: Ek = mw * g * h = 400 * 9.81 * 1.5 * 10 ^ 3 = 5886 * 10 ^ 3 J ≈ 5.9 MJ.

Answer: The potential energy of the indicated balloon became 5.9 MJ.