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Homework Help: Impulse? A strange question

  1. Dec 12, 2013 #1
    1. The problem statement, all variables and given/known data

    The problem is shown below.

    2. Relevant equations

    Conservation of momentum? pi = pf
    ∫Fdt = I ?

    3. The attempt at a solution

    This question is really strange. I have started to do this question for many hours and I don't know how to start it.

    I have tried to list out the equations like Conservation of momentum and ∫Fdt = I , but i don't know how to use this equation! It is very strange ! How to get start? I have also tried using the center of mass but the results are useless!

    Any tips pleases? I have already attempted this equation! But the problem is I don't know how to get start! =(

    Attached Files:

    • Q.png
      File size:
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  2. jcsd
  3. Dec 12, 2013 #2


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    Homework Helper

    You have to use the momentum equation: change of the momentum of the CM is equal to the impulse, and the similar equation for the change of angular momentum, which is equal to the angular impulse ∫τdt,integral of the torque of the applied force. The frame will move as a whole in the direction of the blow and at the same time, rotate about the CM. Knowing the velocity of the CM and the angular velocity with respect to the CM you get the velocity of B.

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