Concept explainers
(a)
The force is conservative.
(a)
Answer to Problem 44P
Yes, the force is conservative.
Explanation of Solution
Conservative forces are the forces whose work done depends on the initial and final position and not on the path followed.
When the particle is pushed by a variable force, work is done on it by the applied force to move it a certain distance ahead.
Write the expression for work done by a variable force to displace a particle.
Here,
Consider force to be constant and solve the above equation (I).
Therefore, the work done is a function of end states only and not the path followed.
Conclusion:
Thus, the force is conservative.
(b)
The work done by
(b)
Answer to Problem 44P
The work done by
Explanation of Solution
Consider three paths across which force acts. The three paths are
Write the expression for the work done along path
Here,
Write the expression for the work done along path
Here,
Write the expression for the work done along path
Here,
The displacement vector
Write the expression for displacement vector.
Conclusion:
Substitute
Simplify the above equation.
Substitute
Substitute
Simplify the above equation.
The work done by the force on the path
The work done by the force on the path
The work done by the force on the path
Thus, the work done by
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Chapter 7 Solutions
Physics For Scientists And Engineers With Modern Physics, 9th Edition, The Ohio State University
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