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Homework Help: Spring acceleration question

  1. May 1, 2005 #1
    two blocks of equal mass are connected by an ideal string.
    the values of m, k1 and k2 are given (k1 > k2 ). Initially, both springs are relaxed. Then the left block is slowly pulled down a distance x and released.
    Find the acceleration of each block.

    sorry about no latex in a hurry :)

    F = ma
    F = -Kx

    ma = -kx

    a = -kx/m

    Since extension is occuring on the left hand side x is positive.
    Since compression takes place on the right hand side x is negitive.

    a = -k(+or-x)/m

    I was in a bit of a hurry but i've tested with some values and it seems ok, but i'd love some help if this is wrong.
  2. jcsd
  3. May 1, 2005 #2


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    Dearly Missed

    Springs or strings or both or none????

    I'm sorry, you haven't been able to pose your problem clearly here.
    Try again..
  4. May 1, 2005 #3
    let me get the diagram it is rather tricky

    Attached Files:

  5. May 1, 2005 #4

    Doc Al

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    Staff: Mentor

    I suggest you start by indentifying all the forces acting on each mass, then write Newton's 2nd law for each separately. Combine those two equations and solve for the acceleration. (Don't forget that they are attached by a string.)
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