Concept explainers
Block A has a mass of 40 kg, and block B has a mass of 8 kg. The coefficients of friction between all surfaces of contact are
(a)
Acceleration of block B
Answer to Problem 12.18P
Acceleration of block B:
Explanation of Solution
Given:
From the constraint of the cord:
Then
And
Now
Then
Or:
First, we determine if the blocks will move for the given value of
For B:
Or:
Now
Or:
For A:
Or:
Now
Equating the two expressions for T,
Or:
Or:
Or:
Since
Now, consider the motion of the blocks.
For B:
Or:
Sliding:
Or:
For A:
Or:
Sliding:
Substituting and using Eq. (1):
Equating the two expressions for T,
Or:
(b)
Tension in the cable
Answer to Problem 12.18P
Tension in the cable:
Explanation of Solution
Given:
Or:
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Chapter 12 Solutions
Vector Mechanics for Engineers: Dynamics
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