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Basic Dynamics

  1. Oct 31, 2007 #1

    After hours of thinking I can't solve this problem:
    The system of the figure is motionless.Then body 2 is released, arriving to the ground in 2 seconds.
    The pulley and the rope have no weight, and there is no friction.
    Find the maximum height that is going to be reached by the base of the body 1.
  2. jcsd
  3. Oct 31, 2007 #2


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    Hi, welcome to PF badbit.

    Can the rope shrink or grow? Otherwise, why wouldn't it be 4 meters?
    (I'm probably missing something here, what does this have to do with dynamics?)
  4. Oct 31, 2007 #3
    Question is fine, "CompuChip". You need to take a coffee-break. [No pun intended.]
    I dunno if the rope can grow, but obviously it can shrink.. or better use, get loose/slack!

    But yes, I too have doubts, if this question has got really something to do with dynamics!

    Use, 2 sec to find the speed of the bodies when body 2 arrives to the ground. (Note both bodies will have same speed till this moment.) After this the rope goes slack, as body 1 continues to move upwards due to inertia. Now, either apply conservation of energy or same kinematics equations, to obtain the furthr height attained by body1.
  5. Nov 1, 2007 #4


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    Ah, now I see it. I just needed some sleep I guess :smile:
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