Concept explainers
(a)
The potential energy at top and the bottom and the change in potential energy.
(a)
Answer to Problem 17PQ
The potential energy at bottom is
Explanation of Solution
The diagram for the position of the child is given in figure 1.
Figure 1
Write the equation of potential energy at bottom.
Here,
Write the equation of potential energy at top.
Here,
Write the expression for the top height.
Here,
Rewrite the expression from equation (II).
Write the expression for the change in potential energy.
Here,
Conclusion:
Substitute
Thus, The potential energy at bottom is
Substitute
Thus, the potential energy at top is
Substitute
Thus, the change in potential energy is
(b)
The potential energy at top and the bottom and the change in potential energy by choosing the top of the slide as reference frame.
(b)
Answer to Problem 17PQ
The potential energy at top is
Explanation of Solution
Write the equation of potential energy at bottom.
Here,
Write the equation of potential energy at bottom.
Here,
Write the expression for the bottom height.
Here,
Rewrite the expression from equation (I).
Write the expression for the change in potential energy.
Here,
Conclusion:
Substitute,
Thus, The potential energy at top is
Substitute,
Thus, the potential energy at bottom is
Substitute,
Thus, the change in potential energy is
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Chapter 8 Solutions
Student Solutions Manual For Katz's Physics For Scientists And Engineers: Foundations And Connections, Volume 1
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