Mission WE4 Mechanical Energy
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Consider the motion of the car (or sled or roller coaster) shown in the diagram below. The kinetic energy (KE) and potential energy (PE) values are shown for various locations. In this example, ____.

The total mechanical energy possessed by an object is the sum of its kinetic energy and potential energy.

Often times an object moves in such a manner as to conserve its total mechanical energy. The kinetic energy and the potential energy may individually change, yet the sum of these two forms of energy (the total amount of mechanical energy) remains a constant value. To determine if the total amount of mechanical energy is conserved, simply sum the KE and PE values for each location. If the sum is the same amount at every indicated location, then total mechanical energy is conserved.