Concept explainers
(a)
The center of mass of the pole vaulter for the given mass distribution of the athlete at a particular instant.
(a)
Answer to Problem 32P
The x and y co-ordinates of center of mass of the pole vaulter are
Explanation of Solution
Given:
A pole vaulter’s distribution of mass with the coordinates. Seven mass points are given. Mass
Formula used:
The x and y coordinates of the center of mass is given as below:
Calculation:
The x coordinate of the center of mass of the pole-vaulter is given as below:
Putting the values of masses and their coordinates we can write as below:
The y coordinate of the center of mass of the pole-vaulter is given as below:
Mass
It is observed that the center of mass of the pole-vaulter lies below the bar at -9.4375 cm.
Conclusion:
The coordinates of the center of mass of the pole-vaulter are
(b)
The height of the bar for the given height of the center of mass.
(b)
Answer to Problem 32P
The height of the bar 6.1 m.
Explanation of Solution
Introduction:
Let say, the center of mass of the pole-vaulter while standing on the ground is 1 meter. As discussed in previous section that the height of the center of mass of the vaulter lies below the bar. Pole vaulter runs with a speed vand hence the Kinetic energy is
The height of the center of mass of the pole-vaulter is 5.1 m. The height of center of mass while standing on the ground is 1m. Hence, the height of the bar will be
Conclusion:
The height of the bar 6.1 m.
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Chapter 5 Solutions
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- University Physics Volume 1PhysicsISBN:9781938168277Author:William Moebs, Samuel J. Ling, Jeff SannyPublisher:OpenStax - Rice University