3. A batter hits a baseball with mass 0.145 kg straight upward with initial speed of 24.0 m/s. (a) How much work has gravity done on the baseball at a height of 20.0 m above the bat? (b) Use work-energy theorem to calculate the speed of the baseball at a height of 20.0 m above the bat. (c) Does your answer to part (b) depend on whether the baseball depend on whether the baseball is moving upward or downward at a height of 20.0 m? Explain.

3. A batter hits a baseball with mass 0.145 kg straight upward with initial speed of 24.0 m/s. (a) How much work has gravity done on the baseball at a height of 20.0 m above the bat? (b) Use work-energy theorem to calculate the speed of the baseball at a height of 20.0 m above the bat. (c) Does your answer to part (b) depend on whether the baseball depend on whether the baseball is moving upward or downward at a height of 20.0 m? Explain.

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter10: Work, Energy And Machines

Section: Chapter Questions

Problem 80A

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