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Homework Help: Pulley system

  1. Nov 26, 2008 #1
    2 masses are tied in the followin configuaration, the 1st with a mass of m1 the 2nd mass of m2, pulleys and ropes have no mass or friction.

    what is the acceleration of each mass, using only parameters g, m1, and m2

    http://picasaweb.google.com/devanlevin/DropBox?authkey=sbH95pBl_D8#5273036312921418818 [Broken]

    not too much i can see from this, i know that |a1|=2|a2|,
    i think that
    1 F=m1a=m1g-T

    2 F=m2a=m2g-2T

    not sure about those though,
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Nov 26, 2008 #2
    looks right to me.
  4. Nov 26, 2008 #3

    Doc Al

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    Staff: Mentor

    So far, so good. But now you need to combine all three equations to solve for a1 & a2 in terms of the given parameters. Hint: Careful with signs. If a1 is down, a2 must be up.
  5. Nov 26, 2008 #4






    is that correct,?? the answer in my textbook is similar, either a mistake on their behalf or im missing something,, their answer is

  6. Nov 26, 2008 #5

    Doc Al

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    Staff: Mentor

    You made an error in this step. Note how the terms in your last equation all have the same units--except one. (When you multiplied by m2, you did not do it completely.)
  7. Nov 26, 2008 #6
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