Concept explainers
(a)
The expression for the distance
(a)
Explanation of Solution
Introduction:
To derive the expression for distance the box slides, the work-energy theorem will be used. Work-energy theorem states that work done by any external force on a body is equal to the change in total energy of that body.
Write the expression for friction force.
Here,
Write the expression for thermal energy.
Here,
Substitute
Write the expression for change in kinetic energy.
Here,
Write the expression for change in gravitational potential energy.
Here,
Write the expression for change in spring potential energy.
Here,
Write the expression of work done by external force.
Here,
Substitute
Substitute
Conclusion:
Thus, the expression for the distance
(b)
The expression of speed for the box slides the distance
(b)
Explanation of Solution
Introduction:
To derive the expression for distance the box slides, the work-energy theorem will be used. Work-energy theorem states that work done by any external force on a body is equal to the change in total energy of that body.
Write the expression for friction force.
Here,
Write the expression for thermal energy.
Here,
Substitute
Write the expression for change in kinetic energy.
Here,
Write the expression for change in gravitational potential energy.
Here,
Write the expression for change in spring potential energy.
Here,
Write the expression of work done by external force.
Here,
Substitute
Substitute
Conclusion:
Thus, the expression of speed for the box slides the distance
(a)
The value of coefficient of friction for
(a)
Explanation of Solution
Introduction:
To derive the expression for distance the box slides, the work-energy theorem will be used. Work-energy theorem states that work done by any external force on a body is equal to the change in total energy of that body.
Write the expression for friction force.
Here,
Write the expression for thermal energy.
Here,
Substitute
Write the expression for change in kinetic energy.
Here,
Write the expression for change in gravitational potential energy.
Here,
Write the expression for change in spring potential energy.
Here,
Write the expression of work done by external force.
Here,
Substitute
Substitute
Conclusion:
Thus, the value of coefficient of friction for
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Chapter 7 Solutions
PHYSICS F/SCI.+ENGRS.,STAND.-W/ACCESS
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