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    Quote Originally Posted by radyk05
    y = yinitial + vy,initial + (1/2) * g * t^2
    I sense a typo.
    Edit:
    Try y = y<sub>0</sub> + v<sub>y,0</sub> * t - (1/2) * g * t²

    Edit2:
    While I'm at it:

    v<sub>x</sub> = dx/dt = v<sub>x,0</sub>
    v<sub>y</sub> = dy/dt = v<sub>y,0</sub> - g * t

    At the max height reached, v<sub>y</sub> = 0, therefore t<sub>max height</sub> = v<sub>y,0</sub>/g
    At that t<sub>max height</sub>, half the horizontal distance is covered, so x<sub>max height</sub> = x<sub>0</sub> + v<sub>x,0</sub> * v<sub>y,0</sub>/g = sin θ * v * cos θ * v /g, which is max for θ = pi/4.
    Now we can clean the mess, and rewrite:
    x = x<sub>0</sub> + sqrt(2)/2 * v * t
    y = y<sub>0</sub> + sqrt(2)/2 * v * t - (1/2) * g * t²

    Now, let's take a point y<sub>h</sub>.
    y<sub>h</sub> = y<sub>0</sub> + sqrt(2)/2 * v * t<sub>h</sub> - (1/2) * g * t<sub>h</sub>²
    h = y<sub>h</sub> - y<sub>0</sub>
    h = sqrt(2)/2 * v * t<sub>h</sub> - (1/2) * g * t<sub>h</sub>²

    We solve this for t<sub>h</sub>, we get:
    t<sub>h,2</sub> = sqrt(2)/2g *(v + sqrt(v² - 4*h*g))
    and
    t<sub>h,1</sub> = sqrt(2)/2g *(v - sqrt(v² - 4*h*g))

    d = x<sub>2</sub> - x<sub>1</sub> = sqrt(2)/2 * v * (t<sub>h,2</sub> - t<sub>h,1</sub>)
    d = sqrt(2)/2 * v * (sqrt(2)/2g *(v + sqrt(v² - 4*h*g)) - sqrt(2)/2g *(v - sqrt(v² - 4*h*g)))
    d = v/g * sqrt(v² -4*h*g)
    Last edited by Endless; 09-24-2005 at 11:04 AM.

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