6.1. Work www.ck12.org
Three different families, each driving a 2000kg rental minivan, decide to drive to a ski resort for winter break. The
first family takes Route A, the second family takes Route B, and the third family takes Route C.
7. How much work does it take to get to the ski resort?
8. How much force does it take the family traveling on Route B to get to the ski resort?
9. How much force does it take the family traveling on Route C to the ski resort?
10. Did the family that took Route A use more, less, or the same amount of energy to get to the ski resort as the
family that took Route B? Explain.
Answer Key
1. Answers will vary.Sample Answer: In physics, work is done whenever a force is applied to move an object a
distance.
2. Yes. Sample Explanation: In physics, work is the done when a force is applied over a distance.
3. No. Sample Explanation: In physics, work is the product of force and distance. The boulder does not move,
so there is no distance. As a result, no work is done. **Misconception Alert: Just because Jeff is tired does
not mean he has done work in the scientific sense.
4. Yes. Sample Explanation: In physics, work is the done when a force is applied over a distance. Joe has applied
a force to move the barbell a distance.
5. No. Sample Explanation: In order for work to be done, the force cannot be perpendicular to the direction
of motion. In this case, the purse is moving rightward and the force is upward. Therefore, the force is
perpendicular to the motion and no work is being done.
6. D
7. W = fd = (20,000 N)(700 m) = 14,000,000 J
8. Work remains the same, 14,000,000 J
14,000,000 J = F(1,150 m)
F = 12,174 N
9. Work remains the same, 14,000,000 J
14,000,000 J = F(940 m)
F = 14894 N
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