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Homework Help: Conservation of Energy

  1. Apr 4, 2009 #1
    1. The problem statement, all variables and given/known data

    2. Relevant equations
    Wgravity = mgh

    3. The attempt at a solution

    I know the gravitational potential energy is different because mgh accounts for mass.
    But the book says that B is correct. I don't know why because isn't the less mass you have the faster you go? 2KE/m=v2
  2. jcsd
  3. Apr 4, 2009 #2


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    Homework Helper

    Step back a bit and look at the equations.

    PE = KE at the bottom.

    m*g*h = 1/2*m*v2

    v2 = 2*g*h

    The mass has canceled out.
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