A 500-g mass is attached to the end of an initially unstretched vertical spring for which k=30 n/m. the mass is then released, so that it falls and stretches the spring. how far will it fall before stopping? (the PEg lost by the mass must appear as PEe)

Arigid tank is divided into two equal parts by a partition. one part of the tank contains 3 kg of compressed liquid water at 400 kpa and 60°c while the other part is evacuated. the partition is now removed, and the water expands to fill the entire tank. determine the entropy change of water during this process, if the final pressure in the tank is 40 kpa. use steam tables.