Initial data: H (dam height) = 20 m; m (mass of falling water) = 1.8 * 10 tons.
Constants: g (acceleration of gravity) = 9.81 m / s ^ 2.
SI system: m = 18 t = 18 * 10 ^ 3 kg.
The work will be done by gravity, you can calculate it using the following formula:
A = Fт * s = m * g * H.
Let’s perform the calculation:
A = 18 * 10 ^ 3 * 9.81 * 20 = 3531600 J ≈ 3.53 MJ.
Answer: When water falls from the dam, work is done at 3.53 MJ.
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