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Homework Help: Tension in ropes connecting blocks

  1. Mar 14, 2005 #1
    The figure shows two 1.0 kg blocks connected by a rope. A second rope hangs beneath the lower block. Both ropes have a mass of 250 g. The entire assembly is accelerated upward at
    3.0 m/s^2
    i found the force that pulls the system to be 32.0N
    However the followup question states:
    What is the tension at the top end of rope 1?

    for a I have
    [tex]
    \sum{}\ = F - T = ma
    [/tex]

    and for b I have

    [tex]
    \sum{}\ = T - W = ma
    [/tex]

    since i knew my a was 3.0 m/s^2 i made the equations equal to each other, to find my tention.
    [tex]
    (T - W)m = (F-T)m
    [/tex]

    I arived at the answer 25.1N which is wrong. i think it may have to do with the fact that the ropes have a mass I thought tension through out a rope was uniform no matter where on the string you are. :grumpy:
     

    Attached Files:

  2. jcsd
  3. Mar 17, 2005 #2
    ok you do it the same way you did the first part, except this time you only count the mass until the end of the first rope. i did this problem a couple of weeks ago. you are doing it on online homework aren't you?
     
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