When defining the gravitational potential energy of an object in a system, the reference point where you define a potential energy can be overlooked. Consider this cartoon you may have seen in Fig. 1. The cartoon is a light-hearted way to look at potential; however, it can be misleading. When considering potential energy in this situation, we examine the ball and Earth together as a system. Potential energy is due to an interaction between the object and what influences it.
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2018
American Association of Physics Teachers
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