11. What happens to the kinetic energy of a moving object if the net work done is positive? c. The kinetic energy remains the same d. The kinetic energy is zero a. The kinetic energy increases b. The kinetic energy decreases 12. When a rock is dropped from height H, it reaches the ground with speed V. Assuming there is no air resistance, from what height should it be dropped so it will reach the ground with twice speed? a. 16H b. 8H c. 4H 13. Which of the following statements is false? a. The unit of energy and work is the same b. The area under a force/distance graph gives the work done c. Electrical energy is converted to mechanical energy by a generator d. Efficiency is the ratio of the useful output energy to the input energy d. 2H

11. What happens to the kinetic energy of a moving object if the net work done is positive? c. The kinetic energy remains the same d. The kinetic energy is zero a. The kinetic energy increases b. The kinetic energy decreases 12. When a rock is dropped from height H, it reaches the ground with speed V. Assuming there is no air resistance, from what height should it be dropped so it will reach the ground with twice speed? a. 16H b. 8H c. 4H 13. Which of the following statements is false? a. The unit of energy and work is the same b. The area under a force/distance graph gives the work done c. Electrical energy is converted to mechanical energy by a generator d. Efficiency is the ratio of the useful output energy to the input energy d. 2H

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter7: Work, Energy, And Energy Resources

Section: Chapter Questions

Problem 60PE: Integrated Concepts (a) Calculate the force the woman in Figure 7.46 exerts to do a push-up at...

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