Answer
(a) The velocity is constant from t = 0 s up to t = 20 s.
(b) The velocity is the greatest at the point t = 27 s.
(c) The velocity is zero at the point t = 37 s.
(d) The object moves in the positive direction until t = 37 s, stops momentarily, and then moves in the negative direction.
Work Step by Step
(a) If the velocity is constant, then the x versus t graph will have a straight line. We can see a straight line on the graph from t = 0 s up to about t = 20 s. During this time period, the velocity is constant.
(b) The velocity is the greatest when the x versus t graph has the greatest positive slope. We can see that the greatest positive slope occurs around the point when t = 27 s.
(c) The velocity is zero when the slope of the x versus t graph is zero. We can see that the slope is positive up to the point when x = 20 m, the velocity is then 0 m/s for a moment, and then the velocity becomes negative. The velocity is zero at the point when t = 37 s.
(d) The object moves in the positive direction until x = 20 m and then the object turns around and moves in the negative direction. So the object moves in the positive direction from t = 0 s up to t = 37 s, and then the object moves in the negative direction from t = 37 s to to = 50 s.
