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Homework Help: Need help - problem newton laws + my try

  1. Sep 4, 2008 #1
    TNX !

    http://img377.imageshack.us/img377/8561/00000qj1.jpg [Broken]
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Sep 4, 2008 #2
    So t =T1. Why is the acceleration 2a in the second equation?
     
  4. Sep 4, 2008 #3
    yes T1=t

    and m1 distance double m2 distance that`s why the acceleration proportion is 2:1

    is that right ?
     
  5. Sep 4, 2008 #4
    No that's not correct where did you get that idea?
     
  6. Sep 4, 2008 #5
    can you be more specific , what is not correct and how to solve the problem ?

    TNX .
     
  7. Sep 4, 2008 #6

    Doc Al

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    Staff: Mentor

    I don't see anything wrong with your equations. Solve them to find a.
     
  8. Sep 4, 2008 #7
    t-m_1gsin30=m_1*2a \ *2
    +
    m_2g-2t=m_2*a


    m_1=m_2 = 5kg


    2t - 2t - 2*5*0.5g + 5g= 20a+5a

    0=25a ====> ??????????????


    the answer in the book is a=2.8

    how is that ????



    plzz help .
     
  9. Sep 4, 2008 #8

    Doc Al

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    Staff: Mentor

    Oops. It looks like the masses are in equilibrium if they are equal. Are you sure you have the masses correct? (Also, what book are you using?)
     
  10. Sep 5, 2008 #9
    yea i am sure .

    the book is classical mechanics by yoram eshel .
     
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