doug (08/13/82)
sorry about that - I just repeated the solution to the first one again! The answer to the 2nd one is that the BOB goes down inside the can. The bouyant force that the water exerts on the BOB = (the density of water) X (the volume of the BOB) X (the acceleration due to gravity). Since gravity is zero inside the free-falling container, so is the bouyant force. Therefore the only force exerted on the BOB is the spring force, which pulls the BOB down of course.