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Homework Help: Two blocks, two pulleys, too confused

  1. Sep 17, 2005 #1
    A block of mass m_1 is attached to a massless, ideal string. This string wraps around a massless pulley and then wraps around a second pulley that is attached to a block of mass m_2 that is free to slide on a frictionless table. The string is firmly anchored to a wall and the whole system is frictionless.

    I've only got as far as figuring out what forces are on each block; the top block has two tensions; one attached to the wall, and the tension that goes to the hanging block. It also has a normal force and the weight. Block two only has tension, normal force (?), and weight.

    Can anyone offer a hint on how to get started finding the acceleration or tension? Thanks, Lily

    Attached Files:

  2. jcsd
  3. Sep 17, 2005 #2
    Write the force equation for the mass hanging down there
    What forces act on it - from below, from above, and what is the resultant of adding those forces??

    Now for the block on the table. Is there any friction? Thus, do u need any vertical forces as such?
    For the horizontal forces, ask yourself what are the force(s) acting on the block, and what will that force(s) result in?
  4. Sep 17, 2005 #3
    Ok, for mass 2, the heavy one, there are two tension forces, but no acceleration, I think. For the hanging mass, just weight down, and the normal/tension force up.
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