What Archimedean force acts on a hollow copper ball with a mass of 890 g

What Archimedean force acts on a hollow copper ball with a mass of 890 g completely immersed in water if the volume of the cavity is 40 cm3?

Data: m (mass of a copper ball) = 890 g (0.89 kg); Vp (volume of the cavity in the ball) = 40 cm3 (40 * 10-6 m3); the ball is completely submerged in water.

Constants: ρm (copper density) = 8900 kg / m3; ρw (water density) = 1000 kg / m3; g (acceleration due to gravity) ≈ 10 m / s2.

1) The total volume of the ball: V = Vm + Vp = m / ρm + Vp = 0.89 / 8900 + 40 * 10-6 = 0.0001 + 40 * 10-6 = 140 * 10-6 m3.

2) The force of Archimedes: Fa = ρw * g * V = 1000 * 10 * 140 * 10-6 = 1.4 N.

Answer: An Archimedes force of 1.4 N. acts on a hollow copper ball.