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Homework Help: Assignment due in less than 1 hr

  1. Nov 14, 2004 #1
    Hey ppl, sorry I was just wondering if anyone knew how to do the question i posted earlier(TWO BLOCKS AND TWO PULLEYS), as I have to submit it and cannot figure it out still!?

  2. jcsd
  3. Nov 14, 2004 #2
    can you post a picture of it. I'm having trouble picturing this system.
  4. Nov 14, 2004 #3
    here's the pic, thanks
  5. Nov 14, 2004 #4
    where? I dont see it as part of your post
  6. Nov 15, 2004 #5
    oh sorry tiger, its okay i had to submit it, thx for your time...i cant get the pic up for some reason..

    Attached Files:

  7. Nov 15, 2004 #6
    never mind must have been my browser
  8. Nov 15, 2004 #7
    well how did you do the first part? it looks right to me. you did:

    [tex]\sum{F} = ma[/tex]

    always always ALWAYS start with this over and over again (or at least try to strat with this). The right hand side will have only ma or 0 thats all it will ever have ( and zero is a particular case of ma--when it is not accelarating, that is, not moving, or constant velocity) The left hand side just sums your forces. So after picking your postitive and negnative on your x and y axis (always do this too) and drew your free body diagram (I hop you did this) you must of did:

    [tex]T + T = m_2a_2[/tex]

    And then you solved for T

    Now for the next part do the same thing

    1) Draw FBD
    2) [tex]\sum{F} = ma[/tex]
    3) [tex]T - m_1g = m_1a_1[/tex]

    And then solve for [tex]a_1[/tex] in terms of everything else they gave you
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