Concept explainers
(a)
Tension in the rope.
(a)
Answer to Problem 175P
The tension is
Explanation of Solution
Using Newton’s second law, write the equation for force on crate on x direction.
Here
Write the equation for force in the y-direction
Here
Write the equation for force on the box in x and y direction
Here
Solve for
Here
Solve for
Eliminate
Conclusion:
Substitute
The tension is
(b)
Time took by the crate to slide down the incline.
(b)
Answer to Problem 175P
The time is
Explanation of Solution
The crate begins from rest. Then initial velocity is zero.
Refer subpart a and write the equation for acceleration
Write the equation of motion for distance covered
Here
Substitute (IV) in (V) and rewrite in terms of
Conclusion
Substitute
The time is
(c)
Force to push the crate.
(c)
Answer to Problem 175P
The force is
Explanation of Solution
Let
Then,
Write the force on the box
Substitute for
Conclusion
Substitute
The force is
(d)
Smallest mass that you could substitute to keep the crate from sliding down the incline.
(d)
Answer to Problem 175P
The mass is
Explanation of Solution
The net force on each object would be zero.
Then net force for the crate,
Here
Force of the box,
Then,
Tension is,
Substitute for
Conclusion
Substitute
The mass is
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Chapter 4 Solutions
Physics
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