本题目来源于试卷: 美国2021年物理杯赛真题 PHYSICS BOWL 2021，类别为 美国物理杯赛(Physics Bowl)
[单选题]
The figure to the right shows the position-time graph of an object traveling in a straight line, starting out moving to the right (the positive x-direction). At which points is the object moving to the left?
A. B and F
B. E and F
C. A, B, and C
D. C, D, and E
E. None of the above
参考答案: D
本题详细解析:
At these points, the object is traveling in the opposite direction of the starting direction.
| 
