Concept explainers
(a)
To show coefficient of kinetic friction
(a)
Explanation of Solution
Given:
The time measure is
Total displacement of the block is
Formula used:
Draw free body diagram of block.
Write expression for net force in the x -direction.
Substitute
Here,
Rearrange above expression for
Substitute
Here,
Calculation:
Write expression for displacement of the block.
Here,
Substitute
Here,
Substitute
Write expression for the displacement of the block.
Substitute
Substitute
Conclusion:
Thus, the coefficient of kinetic friction is
(b)
The value of coefficient of kinetic friction.
(b)
Explanation of Solution
Given:
The block slides
The time taken is
Formula used:
Draw free body diagram of block.
Write expression for net force in the x -direction.
Substitute
Rearrange above expression for
Substitute
Write expression for displacement of the block.
Substitute
Substitute
Write expression for the displacement of the block.
Substitute
Substitute
Calculation:
Substitute
Conclusion:
Thus, the value of the kinetic friction is
(c)
The initial speed of the block
(c)
Explanation of Solution
Given:
Formula used:
Draw free body diagram of block.
Write expression for net force in the x -direction.
Substitute
Rearrange above expression for
Substitute
Write expression for displacement of the block.
Substitute
Substitute
Calculation:
Substitute
Conclusion:
Thus, the initial speed of the block is
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Chapter 5 Solutions
PHYSICS F/SCI.+ENGRS.,STAND.-W/ACCESS
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- Classical Dynamics of Particles and SystemsPhysicsISBN:9780534408961Author:Stephen T. Thornton, Jerry B. MarionPublisher:Cengage Learning