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Mechanical science

  1. Dec 8, 2009 #1
    hi guys im new here so im not sure how this works but anyway im having problem with the question below im not sure how to go about answering it, as our class has had 7 teachers in the last two weeks and havnt even gone threw it but it has to be handed in next week please can some one give me some guidance on this. thank you.
    1. The problem statement, all variables and given/known data

    A pile driver, mass 200kg, is raised to a height of 5m above the pile, mass 1500kg,
    before being released to fall freely so that the driver strikes the pile without
    rebound and together drive the pile into the ground. The distance the pile is
    driven into the ground is 225 mm. Using the principle of conservation of
    momentum determining the ground resistance retarding the driver and the pile.
  2. jcsd
  3. Dec 8, 2009 #2


    User Avatar

    Staff: Mentor

    I'm not sure how to try to answer it either. I've never heard of the term "ground resistance", but maybe it has some definition in your text or class notes?

    How about starting by describing the concept and applicatoin of "conservation of momentum". What does it mean? When can you use it to help you solve problems? What is the momentum of the pile driver right before contact?
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