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Because a difference in position is required when employing the Law of Change for the One-Dimensional Motion with Constant Velocity model, it is important to carefully consider the problem statement, define a useful coordinate system, and accurately assign the initial and final positions. The arbitrariness of choice of power to choose an advantagous origin and direction in the selection of for your coordinates is a feature of all the motion models that can often be exploited to simplify calcuations, but it is important to remember that with great power comes great responsibility: failing to consciously choose a coordinate system can lead to sloppy math and an incorrect solution.
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