When water falls with a mass of 2 tons, a work of 400 kJ is performed. from what height does the water fall?

To determine the height of the fall of water, we apply the formula: A = ΔEp = m * g * h, whence h = A / (m * g).

Values of variables and constants: A – perfect work (A = 400 kJ = 400 * 10 ^ 3 J); m is the mass of water (m = 2 t, in SI m = 2000 kg); g – acceleration due to gravity (g ≈ 10 m / s2).

Let’s make a calculation: h = A / (m * g) = 400 * 10 ^ 3 / (2000 * 10) = 20 m.

Answer: Water fell from a height of 20 m.