A cube of side length 11.0 cm and made of unknown material floats at the surface between water and oil. The oil has a density of 810 kg/m^3.

a)If the cube floats so that it is 70% in the water and 30% in the oil, what is the mass of the cube?
b)What is the buoyant force on the cube?

1 answer

the volume of the cube is 11^3 cc

the mass of the cube is:

11^3x0.7x1 g/cc + 11^3x0.3x0.81 g/cc

bouyant force = mass of cube x g