Coordinate Systems
One of the only complications that can arise in the simple Law of Change for the One-Dimensional Motion with Constant Velocity model is the issue of choice of coordinate system. Because a difference in position is required, 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 origin and direction int the selection of coordinates is actually dangerous in all the motion models, because too much freedom can lead to sloppy math.
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