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Homework Help: Engineering Dynamics, weight is missing, simple problem

  1. Jul 13, 2014 #1
    1. The problem statement, all variables and given/known data
    It is given in the photo

    2. Relevant equations
    They are all given in the photo

    3. The attempt at a solutionI solved exactly the same as in the solution manual, except for the FBD of the slider B, when they write the 2nd Law, they do not input the weight there, only the Tension force by the rod.Why did they do that, that was the part I did not understand. Note: For the B block they use the x-direction as vertical.

    Attached Files:

  2. jcsd
  3. Jul 14, 2014 #2


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    good question, they forgot to include the weight of the block B in the free body diagram. In fact, they didn't include the weight of block A in its free body diagram, although that doesn't affect the solution. But the omission of block B weight was an apparent oversight that does affect the result.
  4. Jul 14, 2014 #3


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    The picture is a top view. The mass of both blocks is relevant, but their weights are not.
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