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Homework Help: Pulley question

  1. Oct 12, 2006 #1
    http://img135.imageshack.us/img135/3314/yeaheg1.th.png [Broken]

    I was wondering if someone could clarify this for me.
    (this system of accelerating, the block on the right is heavier)
    I know that Fnetx = T.

    However, I'm a little confused about why Fnety should be Fw - T as opposed to T - Fw

    When I was doing the free body diagram, for the y coord: T points up and Fw points down, so I was thinking since the standard coord system has up as +y and down as -y then Fnety = T - Fw, unfortunately it seems that it's necessary to reverse that.
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Oct 12, 2006 #2
    probably reversed so that acceleration comes out as a positive value for both blocks.
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