
Concept explainers
(a)
The acceleration of the panel and the tension in the cord after the system released from rest.

Answer to Problem 12.29P
Acceleration of the panel
Tension in the cord
Explanation of Solution
Given information:
Weight of panel
Weight of the counterweight
First, we draw the free body diagram and kinetic diagram of the panel:
F = force exerted by counterweight
Weight
Now, force
Now, computing the forces for counterweight A,
For this we draw the free body and kinetic diagram of the counterweight A;
Hence, from the above diagram it is clear that the acceleration component of counterweight A has two components.
Now,
Now, adding equation (1), (2) and (3);
Now, Tension in the cord from equation (3),
(b)
The acceleration of the panel and the tension in the cord after the system released from rest.

Answer to Problem 12.29P
Acceleration of the panel
Tension in the cord
Explanation of Solution
Given information:
Weight of panel
Weight of the counterweight
First, we draw the free body diagram and kinetic diagram of the panel:
F = force exerted by counterweight.
Weight
Now, force
Now, computing the forces for counterweight A,
For this we draw the free body and kinetic diagram of the counterweight A;
Now, adding equation (1) and (2);
Now, Tension in the cord from equation (1),
(c)
The acceleration of the panel and the tension in the cord after the system released from rest.

Answer to Problem 12.29P
Acceleration of the panel
Tension in the cord
Explanation of Solution
Given information:
Weight of panel
Weight of the counterweight
First, we draw the free body diagram and kinetic diagram of the panel:
F = force exerted by counterweight
Weight
Now, force
Since, panel is accelerated to the left, there is no force exerted by the panel on counterweight hence;
Now, computing the forces for counterweight A,
For this, we draw the free body and kinetic diagram of the counterweight A;
Now, adding equation (1) and (2);
Now, Tension in the cord from equation (1),
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Chapter 12 Solutions
Vector Mechanics for Engineers: Dynamics
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