In the water from a depth of 5 m, a stone with a volume of 0.6 m3 is raised to the surface.

In the water from a depth of 5 m, a stone with a volume of 0.6 m3 is raised to the surface. The density of the stone is 2500 kg / m3. Determine the work of lifting the stone.

h = 5 m.

V = 0.6 m3.

ρк = 2500 kg / m3.

ρw = 1000 kg / m3.

g = 9.8 m / s2.

A -?

The work of lifting stone A will be determined by the formula: A = F * S, where F is the force that lifts the stone, S is the movement of the stone.

F = m * g – Farch.

m = V * ρк.

The buoyancy force of Archimedes is determined by the formula: Farch = ρw * g * V. Where ρw is the density of the liquid in which the body is immersed, g is the acceleration of gravity, V is the volume of the immersed part of the body in the liquid.

S = h.

A = (V * ρк * g – ρв * g * V) * h = = (ρк – ρв) * h * g * V.

A = (2500 kg / m3 – 1000 kg / m3) * 5 m * 0.6 m3 * 9.8 m / s2 = 44100 J.

Answer: to raise the stone, you need to do the work A = 44100 J.