Concept explainers
(a)
The magnitude of force P.
Answer to Problem 12.28P
Explanation of Solution
Given information:
Mass of block A
Mass of block B=C
Time
Let the position co-ordinate be Y and it is positive towards downwards.
Now, constraint of cord AD:
Then,
Similarly, constraint of cord BC:
Then,
Now, from equation (1) and (2);
As all of the forces are constant then, we have uniformly accelerated motions.
Then,
Now, calculate all the forces for pulley D,
Now, calculate all the forces for block A, for this the draw the free body and kinetic diagram of the block A:
Calculate all the forces for block C, for this the draw the free body and kinetic diagram of block C:
Calculate all the forces for block B, for this the draw the free body and kinetic diagram of block B:
Substituting the values of equation (4) and (5) into equation (3);
Putting all the values in equation (6);
(b)
The tension in cord AD.
Answer to Problem 12.28P
Explanation of Solution
Given information:
Mass of block A
Mass of block B=C
Time
Let the position co-ordinate be Y and it is positive towards downwards.
Now, constraint of cord AD:
Then,
Similarly, constraint of cord BC:
Then,
Now, from equation (1) and (2);
As all of the forces are constant then we have uniformly accelerated motions.
Then,
Now, calculate all the forces for pulley D,
Now, calculate all the forces for block A, for this the draw the free body and kinetic diagram of the block A:
Calculate all the forces for block C, for this the draw the free body and kinetic diagram of the block C:
Substituting the values of equation (4) and (5) into equation (3);
Now, tension in cord AD;
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Chapter 12 Solutions
Vector Mechanics For Engineers
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