Concept explainers
(a)
The potential energy function
(a)
Answer to Problem 50P
The potential energy function
Explanation of Solution
Work done by internal forces of a system is equal to negative of change in potential energy of the system.
Write the expression for the conservation of energy.
Here,
Simply the above equation for potential energy.
Write the expression for the change in potential energy.
Here,
Write the expression for the internal energy.
Here,
Substitute
Conclusion:
Substitute
Thus, the potential energy function
(b)
The change in potential energyas the particle moves from
(b)
Answer to Problem 50P
The change in potential energyas the particle moves from
Explanation of Solution
Write theinitial potential energy expression.
Here,
Write thefinal potential energy expression.
Here,
Write the expression for the change in potential energy.
Here,
Substitute
.
Conclusion:
Substitute
Thus, the change in potential energyas the particle moves from
(c)
Thechange in kinetic energy as the particle moves from
(c)
Answer to Problem 50P
The change in kinetic energy as the particle moves from
Explanation of Solution
From the work energy theorem the change in kinetic energy is the work done by the force on the particle.
Here
Substitute
Simplify the above equation for change in kinetic energy.
Conclusion:
Substitute
Thus, the change in kinetic energy as the particle moves from
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Chapter 7 Solutions
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