A cube is placed in a pool of water. If the cube is 48 cm long on each side, what is the weight of the cube? (Use 1000 kg/m3 for the density of water)

Answer 1

Solution:

When the cube is placed in the water, the buoyant force is the volume of the cube displaced by water.

The volume of the cube is V = [48 cm ( m / 100cm)]³ = 0.1106 m³

The buoyant force = (Density of water * Volume of cube) ( g )

= [1000 kg/m³ ( 0.1106 m³)] 9.81 m/s² = 1084.98 kg-m/s² = 1085 N

For the cube to float, the buoyant force has to equal the weight of the cube

Weight of cube = buoyant force = 1085 N