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Homework Help: Find the force

  1. Oct 27, 2006 #1
    My problem is to find the force needed to give the system of bodies a velocity of 30 ft/s after moving 20 ft. from rest.

    Can anyone help me with this? All i have done is found EFx and EFy for the 50lb. force.
     

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  3. Oct 27, 2006 #2

    radou

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    Can't see the attachment though, but try to use the fact that the work done by that unknown force equals the change of kinetic energy. I hope this helps.
     
  4. Oct 27, 2006 #3
    so the work equals 0.2??? r u sure
     
  5. Oct 27, 2006 #4

    radou

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    No, I'm not sure until I see the diagram. :smile:
     
  6. Oct 27, 2006 #5
    this is thr diagram
     

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  7. Oct 27, 2006 #6

    radou

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    I can't see it again - perhaps there's a problem with my computer, so someone other will be able to reply.
     
  8. Oct 27, 2006 #7
    ok. thankx for ya help thou
     
  9. Oct 28, 2006 #8
    can someone help me with this problem
     
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