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A girl operates a radio-controlled model car in a vacant parking lot. The girl’s position is at the origin of the xy coordinate axes, and the surface of the parking lot lies in the x–y plane. She drives the car in a straight line so that the x coordinate is defined by the relation x(t) = 0.5t3 − 3t2 + 3t + 2, where x and t are expressed in meters and seconds, respectively. Determine (a) when the velocity is zero, (b) the position and total distance traveled when the acceleration is zero.
Fig. P11.7
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