The system can be considered as the suffix we give to a collection of objects. These objects are modeled by the many standard equations. When we describe the motion of an object using the theory of conservation of energy, then the system is supposed to include the object of interest and all other objects that it interacts with.
Mechanical energy can be described as the sum of the potential energy and kinetic energy in a system.
When energy is conserved, it is possible to set up equations since we can equate the sum of the different forms of energy in a system. This allows us to solve the equations for velocity, distance, or any other parameter on which the energy depends. Another advantage of using the theorem of conservation of energy to solve problems is that even if we don’t know all the necessary variables to solve a certain type of problem, it might still be useful in understanding a situation, even in terms of variables.
The perpetual motion discusses the concept of a machine which continues its motion forever with a condition that there won’t be any reduction in speed. It is the dream of modern science. Though it seems really interesting such a machine cannot really work according to physics we have explored. In fact, even if such a machine were to exist, it wouldn’t be useful to anyone is what has been discovered .apparently, it would have no ability to do work.