1. The problem statement, all variables and given/known data A 320 kg wooden raft floats on a lake in equilibrium. When a 75 kg man steps carefully onto the raft, it floats 3.5 cm deeper into the water. When he steps off, the raft oscillates for a while. (a) The buoyant force of the water on the raft is a restoring force that is directly proportional to how deep the raft sits in the water. In this way, the water acts like a mechanical spring. Calculate the force constant of this spring. 2. Relevant equations 3. The attempt at a solution I am not sure how to get the force constant out of this, as if it were a spring. k = f/displacement ?