Practice Problems Sol2

Problem 2 Solution: The position-time graph on the right shows the motion of three different pedestrians walking along a sidewalk, creatively named A, B and C.

a) Compare the starting positions for A, B, and C. B starts nearest the origin, A starts away from the origin and C starts even farther away. b) Compare the velocities for A, B, and C. A and B have identical velocities traveling away from the origin since their graphs have the same positive slope. C has a greater velocity than A and B since its slope is steeper, but since its slope is negative, its motion is toward the origin. c) Compare the displacements for A, B, and C for the motion depicted on the graphs. A and B have identical displacements (change in position) and C has a larger displacement than A and B. d) Explain what crossings x and y represent. Crossing x corresponds to when pedestrians A and C are at the same place at the same time and crossing y corresponds to when pedestrians B and C are at the same place at the same time.