1. The problem statement, all variables and given/known data Two masses A, and B both sit on a vertical spring. If the spring is compressed then released, why do A and B rise to the same height? (the mass of A is greater than that of B) 2. Relevant equations P = mgh S = 1/2kx2 K = 1/2mv2 3. The attempt at a solution Both masses rise to the same height, I treated the two blocks as a system, because the spring propels them both in the air. Why is this? How much energy does each block have?