Assume a strong permanent magnet is suspended by a string over a metallic object. The magnet is slowly lowered until the object is attracted to the magnet. For this to occur the object acquired both kinetic and potential energy. Since the object comes to rest upon hitting the magnet, I assume the kinetic energy is dissipated as heat within the magnet. But considering only the closed system of the magnet and the object, the end result is a magnet that has acquired heat energy and an object that has acquired potential energy. Please explain how energy is conserved in this closed system. Thanks for helping resolve this for a group of us with too much time on our hands.