Calculate the difference in pressure between the top and bottom surfaces of a cube of size 10x10x10 cm at a depth of 20 cm in water. At 100 cm? I know that P=F/A . and in this case force is referring to buoyant force so F=ρgV. And the density of water is just 1000 kg/m^3. And the area of the cube is just 1000 m^3. But where does the depth of the water come into play?