Final answer:
The conservation of mechanical energy principle states that in a closed system, free of dissipative forces, the sum of kinetic and potential energy remains constant.
Step-by-step explanation:
The conservation of mechanical energy is defined as a principle stating that the total mechanical energy in a closed system, in the absence of dissipative forces like friction or air resistance, remains constant. Mechanical energy itself is the sum of kinetic energy and potential energy; this relationship can be expressed as KE + PE = constant. During any process, energy may transform from one form to another—such as from potential to kinetic—but the total amount of mechanical energy will be conserved as long as no energy is lost to the surroundings.
Mechanical energy is an important concept when analyzing physical systems, whether it's a simple pendulum, a mass-spring oscillator, or a charged particle in an electric field. In each case, the internal energy and the configuration of the system contribute to changes in the system's mechanical energy. However, these changes are governed by conservation laws that maintain the overall energy balance within the system.