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Calculus - Physics question

  1. Aug 2, 2010 #1
    Ok here is my question:

    Potential energy = mgh
    Kinetic energy = 1/2mv^2
    mgh = 1/2mv^2, solving for v you get v = sqrt(2gh)

    Now I know v is the same as dx/dt so if I substite in dx/dt for v :

    dx/dt = sqrt(2gh)

    Multiply by dt:
    dx = sqrt(2gh) * dt
    x = t*sqrt(2gh)

    This should be right, but for some reason it doesnt work when I check it with the well known x = x0 + v0t + 1/2at^2 formula, what am I doing wrong?
  2. jcsd
  3. Aug 2, 2010 #2


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    I'm assuming that h is supposed to be the distance fallen? That would in fact be the same as your variable x then, not a constant
  4. Aug 3, 2010 #3
    ooh I see thanks!
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