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Homework Help: Simple Work and Energy question

  1. Oct 7, 2008 #1
    A) the force required to give a helicopter of a mass M an acceleration of .10g upward.
    B) Find the work done by this force as the helicopter moves a distance of h upward

    I'm not incompetent or totally clueless about this.I know that F=ma and W=Fx

    So, my solutions:

    a) F=ma
    F= .10Mg

    b) W=Fx

    But the answer in the back of my book has a) 1.10Mg B) 1.10Mgh so either I'm missing some crucial step, or my book has a typo

    help please?
  2. jcsd
  3. Oct 7, 2008 #2


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    Homework Helper

    Unfortunately you forgot that the Helicopter has a weight of m*g.
    To accelerate it another .1g means that it must overcome the original m*g and then add the extra .1*m*g.
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