Question
A block with mass M is connected by a massless spring with stiffness constant k to a rigid wall and moves without friction on a horizontal surface. The block oscillates with small amplitude A about an equilibrium position x0. Consider two cases: (i) when the block is at x=x0+A. In both cases, a particle with mass m(<M) is softly placed on the block after which they stick to each other. Find the total energy in both cases.