Concept explainers
(a)
Draw free body diagram of each block.
(a)
Answer to Problem 53P
The free body diagram of mass
The free body diagram of mass
Explanation of Solution
The free body diagram is the graphical illustration used to visualize the movements and forces applied on a body.
Let
The free body diagram of mass
The free body diagram of mass
Conclusion:
Therefore, the free body diagram of mass
(b)
The net force on the system of two blocks.
(b)
Answer to Problem 53P
The net force on the system of two blocks is
Explanation of Solution
From the Figure 1, write the expression for net force action on the mass
Here,
From the Figure 2, write the expression for net force action on the mass
Here,
So the net force on the system is the sum of net force on the each block.
Since contact force acting on each mass is equal.
The net force on the system of block is equal to the magnitude of force
Conclusion:
Therefore, the net force on the system of two blocks is
(c)
The net force on the mass
(c)
Answer to Problem 53P
The net force on the mass
Explanation of Solution
From the Figure 1, write the expression for net force action on the mass
The net force on the mass
Conclusion:
Therefore, the net force on the mass
(d)
The net force acting on the
(d)
Answer to Problem 53P
The net force acting on the
Explanation of Solution
From the Figure 2, write the expression for net force action on the mass
The net force acting on the
Conclusion:
Therefore, the net force acting on the
(e)
Newton’s second law in the
(e)
Answer to Problem 53P
Newton’s second law in the
Explanation of Solution
The blocks are pushed to the right, the acceleration on each block is same and the block exerts equal and opposite forces on each other, so these forces have the same magnitude.
Write the expression for Newton’s second law in the
Here,
Write the expression for frictional force.
Here,
Use equation (III) and (IV) in (I).
Use equation (III) and (IV) in (II).
Conclusion:
Therefore, Newton’s second law in the
(f)
Acceleration of the blocks.
(f)
Answer to Problem 53P
Acceleration of the blocks is
Explanation of Solution
Add equation (V), and (VI), and solve for
Conclusion:
Therefore, the acceleration of the blocks is
(g)
The magnitude of contact force
(g)
Answer to Problem 53P
The magnitude of contact force
Explanation of Solution
Solve equation (IV) for
Use equation (VII) in (VIII).
Simplify the equation (IX).
Conclusion:
Therefore, the magnitude of contact force
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Chapter 5 Solutions
Principles of Physics: A Calculus-Based Text
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