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Homework Help: Finding the tension in a string

  1. Nov 12, 2008 #1
    1. The problem statement, all variables and given/known data
    Two blocks weighing 250 N and 350 N are connected by a string that passes over a massless pulley. What is the tension in the string?

    2. Relevant equations
    T= (2*m1*m2)/(m1+m2)*9.8m/s2

    3. The attempt at a solution
    m1 = 250/9.8 = 25.5
    m2 = 350/9.8 = 35.7

    T = (2*25.5*35.7)/(25.5+35.7)*9.8 = 291 N

    Doesn't seem right. Can someone tell me what I did wrong?
  2. jcsd
  3. Nov 12, 2008 #2


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    Staff Emeritus
    Science Advisor
    Homework Helper

    It looks right to me. The tension is somewhere in between the two weights, as it should be.

    Just watch the sig figs, if your teacher (hopefully) cares about that.
  4. Nov 12, 2008 #3
    Alright, well the answer is 290 so I probably just rounded off too much (like you said).

    I was just wondering if I used the right formula but it seems that I did.

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