A 2m * 3m * 5m water tank is evenly lowered on a vertical cable.

A 2m * 3m * 5m water tank is evenly lowered on a vertical cable. What work does the gravity force on the water do when the tank is lowered by 4 m?

We express the work of gravity by the formula:
A = F * S, where F is the acting gravity (F = Ft = m * g (m is the mass of the water tank (m = ρ * V, ρ is the density of water (ρ = 1000 kg / m ^ 3), V is the volume of water in the tank (V = 2 * 3 * 5 m ^ 3 = 30 m ^ 3)), g is the acceleration of gravity (we take g = 9.8 m / s ^ 2), S is the movement of the water tank ( S = 4 m).
Let’s calculate the work of gravity:
A = F * S = m * g * S = ρ * V * g * S = 1000 * 30 * 9.8 * 4 = 1176000 J = 1.176 MJ.
Answer: The work of gravity is 1.176 MJ.