Final answer:
In a Newtonian demonstrator, potential energy at the top of a sphere's swing is converted to kinetic energy as it falls. The kinetic energy then transfers through the other spheres and causes the opposite sphere to swing upward, converting kinetic energy back into potential energy. This demonstrates the continual exchange between potential and kinetic energy.
Step-by-step explanation:
The Newtonian demonstrator, commonly known as Newton's cradle, is a device that illustrates the principles of conservation of momentum and energy through a series of swinging spheres. In this device, potential energy and kinetic energy play crucial roles. When one sphere at the end is lifted and released, it has gravitational potential energy due to its position. As it swings downwards, this potential energy is converted into kinetic energy, which is the energy of motion. Upon impacting the stationary spheres, the kinetic energy is transferred through the spheres and causes the sphere at the opposite end to swing upward and gain potential energy.
In summary, when a sphere reaches the top of its swing, it has maximum potential energy and minimal kinetic energy. When passing through the lowest point of its swing, it has maximum kinetic energy and minimal potential energy. The transformation between potential energy (energy stored in the spring) and kinetic energy (energy of the wagons) continues back and forth, demonstrating a perpetual exchange between these two forms of energy, unless external forces like friction and air resistance eventually cause the system to come to rest.