a solid cube of side l floats on water with 20% of its volume under water. Cubes identical to it are piled one by one on it. Assumes that the cubes do not slip or topple and contact between their surfaces is perfect. How many cubes are required to submerge one cube completly?
1 answer
Five, counting the submerged cube. The cubes have 1/5 the density of water. Five of them have a weight of 5*0.2*M*g, where M is the mass of one cube, IF it were water. That weight is balanced by the buoyancy force of a single cube, M*g.
1 answer