Concept explainers
(a)
The value of
Answer to Problem 74QAP
The value of
Explanation of Solution
Given data:
Formula Used:
Newton's second law:
Calculation:
We'll use two different but related coordinate systems for the two blocks. For block
We can draw free-body diagrams and apply Newton's second law in component form for both blocks.
The tension acting on each block will be identical in magnitude.
Since block
Since, both blocks are at rest, which means the acceleration of each block is zero and we can calculate
.
Free-body diagram of
Newton's second law for
Free-body diagram of
Conclusion:
For two blocks to be in equilibrium the value of
(b)
The magnitude of acceleration of two blocks if the system can move.
Answer to Problem 74QAP
The magnitude of acceleration of two blocks
Explanation of Solution
Given data:
Formula Used:
Newton's second law:
Calculation:
We'll use two different but related coordinate systems for the two blocks. For block
We can draw free-body diagrams and apply Newton's second law in component form for both blocks.
The tension acting on each block will be identical in magnitude.
Since block
Since,
The magnitude of the acceleration will be the same for each block because they are joined together with a string.
Free-body diagram of
Free-body diagram of
Newton's second law for
Conclusion:
If the system can move the magnitude of acceleration of two blocks is
(c)
The direction of
Answer to Problem 74QAP
The direction of
Explanation of Solution
Given data:
Formula Used:
Newton's second law:
Calculation:
We'll use two different but related coordinate systems for the two blocks. For block
We can draw free-body diagrams and apply Newton's second law in component form for both blocks.
The tension acting on each block will be identical in magnitude.
Since block
Since,
Free-body diagram of
Free-body diagram of
Newton's second law for
Since
Conclusion:
As we have value of
(d)
The distance to which block
Answer to Problem 74QAP
The distance to which block
Explanation of Solution
Given data:
Formula Used:
Newton's second law:
And
Calculation:
We'll use two different but related coordinate systems for the two blocks. For block
We can draw free-body diagrams and apply Newton's second law in component form for both blocks.
The tension acting on each block will be identical in magnitude.
Since block
Since,
If the acceleration is constant, we can use the constant acceleration equations to calculate how far
Free-body diagram of
Free-body diagram of
Newton's second law for
By using the constant acceleration equations to calculate how far
Conclusion:
Thus in
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Chapter 4 Solutions
COLLEGE PHYSICS
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