An object moves along a straight line so that its position as a function of time would appear on a position–time graph as follows (graph not shown):
• From t=0s to t=10s the object moves uniformly from x=0m to x=25m.
• From t=10s to t=15s the object remains at x=25m.
• From t=15s to t=25s the object moves uniformly to x=10m.
(a) Describe the object’s net displacement between t=0s and t=25s.
(b) Determine the average velocity of the object over each of the three time intervals described above, stating both magnitude and sign.
(c) Explain how the slopes of the corresponding segments on the position–time graph relate to the average velocities calculated in part (b).