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Homework Help: What is the magnitude of tension in the string supporting the pulley

  1. Aug 16, 2011 #1
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    If mass 1 is 5 kg, and mass 2 is 3 kg, what is the magnitude of tension in the string supporting the pulley, T1?

    The answer is 74 N.

    What I presume they did was to find tension in the string and then double that to get ~74 Newtons.

    My question is: why isn't T1 simply the weight of the two blocks???
     
  2. jcsd
  3. Aug 16, 2011 #2

    PhanthomJay

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    Yes, using a FBD of the pulley in equilibrium.
    It would be if the system was in equilibrium. Is it??
     
  4. Aug 17, 2011 #3
    O.k. I think I see what you are saying. Thank you
     
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