Original Project
Force and Motion
Item FM090002: A wagon that is being pulled with a constant force can move faster than the person pulling it if the force of the pull is greater than the force of friction on the wagon.
A girl is pulling a wagon on level ground. She is running at constant speed and pulling on the wagon with constant force.
Could the wagon move faster than the girl is running?
- Yes, but only if she wasn’t running fast.
- Yes, but only if she pulled harder and harder.
- Yes, but only if the force of her pull on the wagon was greater than the force of friction on the wagon.
- No, because if she was pulling with constant force, the wagon would have to move at constant speed.
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
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|---|---|---|---|---|---|---|---|---|
| n = 1779 |
6–8 n = 1117 |
9–12 n = 654 |
Male n = 824 |
Female n = 909 |
English n = 1567 |
Other n = 177 |
||
| A. | Yes, but only if she wasn’t running fast. | 7% | 7% | 8% | 8% | 6% | 7% | 7% |
| B. | Yes, but only if she pulled harder and harder. | 18% | 20% | 14% | 19% | 17% | 18% | 17% |
| C. | Yes, but only if the force of her pull on the wagon was greater than the force of friction on the wagon. | 25% | 23% | 28% | 21% | 29% | 25% | 27% |
| D. | No, because if she was pulling with constant force, the wagon would have to move at constant speed. | 50% | 50% | 50% | 52% | 48% | 50% | 49% |