Passage Problems The energy in a batted baseball comes from the power delivered while the bat is in contact with the ball. The most powerful hitters can supply some 10 horsepower during the brief contact time, propelling the ball to over 100 miles per hour. Figure 6.20 shows data taken from a particular hit, giving the power the bat delivers to the ball as a function of time. Power (kW) 0 0.05 0.1 Time (s) 0.15 0.2 FIGURE 6.20 Passage Problems 92-95 92. Which of the following is greatest at the peak of the curve? a. the ball's kinetic energy b. the ball's speed c. the rate at which the bat supplies energy to the ball d. the total work the bat has done on the ball 93. The ball has its maximum speed at about a. 85 ms. b. 145 ms. c. 185 ms. d. whenever the force is greatest. 94. As a result of being hit, the ball's kinetic energy increases by about a. 550 J. b. 1.3 kJ. c. 7.0 kJ. d. You can't tell because you don't know its speed coming from the pitcher. 95. The force on the ball is greatest approximately a. at 185 ms. b. at the peak in Fig. 6.20. c. before the peak in Fig. 6.20. d. after the peak in Fig. 6.20 but before 185 ms.

Passage Problems The energy in a batted baseball comes from the power delivered while the bat is in contact with the ball. The most powerful hitters can supply some 10 horsepower during the brief contact time, propelling the ball to over 100 miles per hour. Figure 6.20 shows data taken from a particular hit, giving the power the bat delivers to the ball as a function of time. Power (kW) 0 0.05 0.1 Time (s) 0.15 0.2 FIGURE 6.20 Passage Problems 92-95 92. Which of the following is greatest at the peak of the curve? a. the ball's kinetic energy b. the ball's speed c. the rate at which the bat supplies energy to the ball d. the total work the bat has done on the ball 93. The ball has its maximum speed at about a. 85 ms. b. 145 ms. c. 185 ms. d. whenever the force is greatest. 94. As a result of being hit, the ball's kinetic energy increases by about a. 550 J. b. 1.3 kJ. c. 7.0 kJ. d. You can't tell because you don't know its speed coming from the pitcher. 95. The force on the ball is greatest approximately a. at 185 ms. b. at the peak in Fig. 6.20. c. before the peak in Fig. 6.20. d. after the peak in Fig. 6.20 but before 185 ms.

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter7: Work And Kinetic Energy

Section: Chapter Questions

Problem 67P: A person in good physical condition can put out 100 W of useful power for several hours at a...

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