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Homework Help: Perspective on a FBD?

  1. Feb 28, 2010 #1
    1. The problem statement, all variables and given/known data
    A cup is spinning around on a Lazy Susan...

    2. Relevant equations

    3. The attempt at a solution
    My question is about the perspective. The picture on my book is like this:

    So should I draw the free body diagram from this perspective, with the weight by the Earth on the cup pointing down, or from the top down perspective where I can see the friction force?
  2. jcsd
  3. Feb 28, 2010 #2


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    Homework Helper

    You can go either way. Show forces into the page as an X in a circle.
    The friction force would be toward the center of the turntable, so would look the same in either view.
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