Final answer:
A free falling object's potential energy is converted to kinetic energy as it falls until it reaches the ground, where both potential and kinetic energy become zero and are dissipated into other forms such as heat and sound.
Step-by-step explanation:
When a freely falling object reaches the ground, its potential energy is converted to kinetic energy as it falls. Once it impacts the ground, both potential and kinetic energy effectively become zero because the object is no longer moving, and it is at its minimum height relative to the point from which it fell. In the process of falling, the conservation of energy principle dictates that the energy is not lost but transformed. If there is no air resistance, as the object descends, its potential energy decreases while its kinetic energy increases, and the total mechanical energy of the object remains constant. However, upon contact with the ground, the kinetic energy is rapidly dissipated as other forms of energy, typically sound, heat, and deformation energy.