40. A pendulum, comprising a light string of length L and a S small sphere, swings in the vertical plane. The string hits a peg located a distance d below the point of suspension (Fig. P8.40). (a) Show that if the sphere is released from a height below that of the peg, it will return to this height after the string strikes the peg. (b) Show that if the pendu- Peg lum is released from rest at the hor- izontal position (0 = 90°) and is to swing in a complete circle centered on the peg, the minimum value of d must be 3L/5. %3D Figure P8.40

40. A pendulum, comprising a light string of length L and a S small sphere, swings in the vertical plane. The string hits a peg located a distance d below the point of suspension (Fig. P8.40). (a) Show that if the sphere is released from a height below that of the peg, it will return to this height after the string strikes the peg. (b) Show that if the pendu- Peg lum is released from rest at the hor- izontal position (0 = 90°) and is to swing in a complete circle centered on the peg, the minimum value of d must be 3L/5. %3D Figure P8.40

Physics for Scientists and Engineers with Modern Physics

10th Edition

ISBN:9781337553292

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter8: Conservation Of Energy

Section: Chapter Questions

Problem 40AP: A pendulum, comprising a light string of length L and a small sphere, swings in the vertical plane....

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Check Your Understanding When the length of the spring in Example 8.3 changes from an initial value of 22.0 cm to a final value, the elastic potential energy it contributes changes by 0.0800 J. Find the final length.
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A pendulum, comprising a light string of length L and a small sphere, swings in the vertical plane. The string hits a peg located a distance d below the point of suspension (Fig. P8.40). (a) Show that if the sphere is released from a height below that of the peg, it will return to this height after the string strikes the peg. (b) Show that if the pendulum is released from rest at the horizontal position ( = 90) and is to swing in a complete circle centered on the peg, the minimum value of d must be 3L/5. Figure P8.40
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