Concept explainers
(a)
The initial tension in the cable.
Answer to Problem 12.72P
The initial tension:
Explanation of Solution
Given information:
The velocity of block A is
Mass of the pulley and the effect of the friction is negligible.
From results of part (b), the initial acceleration of block A:
Calculations:
From the free body and kinetic diagram of block A:
Conclusion:
The initial tension in the cable is
(b)
The initial acceleration of block A.
Answer to Problem 12.72P
The initial acceleration of block A:
Explanation of Solution
Given information:
The figure:
The velocity of block A is
Mass of the pulley and the effect of the friction is negligible.
Calculation:
Draw the free body and kinetic diagram of block A:
Draw the free body and kinetic diagram of block B:
Representing the components of acceleration of block A as shown in the below diagram:
Conclusion:
The initial acceleration of block A:
(c)
The initial acceleration of block B.
Answer to Problem 12.72P
The initial acceleration of block B:
Explanation of Solution
Given information:
The velocity of block A is
Mass of the pulley and the effect of the friction is negligible.
From results of part (b), the initial acceleration of block A:
Calculations:
From eq. (6) defined in part (b):
Conclusion:
The initial acceleration of block B is
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Chapter 12 Solutions
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