A constant horizontal force of 28 N is exerted by a string attached to a 8-kg block being pulled across a tabletop. The block also experiences a frictional force of 6 N due to contact with the table.
- a. What is the horizontal acceleration of the block?
- b. If the block starts from rest, what will its velocity be after 3 seconds?
- c. How far will it travel in these 3 seconds?
(a)
The horizontal acceleration of the block if a horizontal force of
Answer to Problem 1SP
The horizontal acceleration of the block if a horizontal force of
Explanation of Solution
Given info: The horizontal force is
Write the expression for the net horizontal force.
Here,
The negative sign indicate that frictional force is opposite to horizontal force
Substitute
Write the expression for the acceleration of the horizontal acceleration of the block.
Here,
Substitute
Conclusion:
Thus, the horizontal acceleration of the block if a horizontal force of
(b)
Velocity of the block after
Answer to Problem 1SP
Velocity of the block after
Explanation of Solution
Given info: The time after which velocity is to be find is
Write the expression for the equation of motion of the block.
Here,
Substitute
Conclusion:
Thus, the velocity of the block after
(c)
The distance it travels in
Answer to Problem 1SP
The distance it travels in
Explanation of Solution
Write the expression for the distance travelled by the block.
Here,
Substitute
Conclusion:
Thus, the distance it travels in
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Chapter 4 Solutions
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