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Because the Work-Energy Theorem and the principle Law of Change for the Mechanical Energy, External Work, and Internal Non-Conservative Work model involve only the initial and final energies of the system, it is useful to devote considerable attention to understanding the system's configuration at those times. It is customary to sketch the system in its initial and final configurations, labeling the quantities that are relevant for the kinetic and potential energies of the system.
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Model: Mechanical Energy, External Work, and Internal Non-Conservative Work Approach:...
Model: Mechanical Energy, External Work, and Internal Non-Conservative Work.
Approach:...