Uneven start/end points (2D Kinematics)

AI Thread Summary
A diver springs from a 3-meter-high board and contacts the water at a speed of 9.30 m/s, making an angle of 84.0º with the horizontal. The problem involves determining her initial velocity using kinematic equations, specifically h = v(i) * t - 1/2at^2. The user attempted to solve the quadratic equation derived from this kinematic relationship but expressed uncertainty about calculating the time due to the initial height. The solution was reached by isolating the relevant portion of the parabola to find the initial velocity. The discussion highlights the application of 2D kinematics in solving projectile motion problems.
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Homework Statement


A diver springs upward from a board that is 3 meters above the water. At the instant she contacts the water her speed is 9.30 m/s and her body makes an angle of 84.0º with respect to the horizontal surface of the water. Determine her initial velocity, both magnitude and direction.

Homework Equations


h = v(i) * t - 1/2at^2
t(half) = (v * sin(x))/g
d = (v^2 * 2sin(x) * cos(x))/g

The Attempt at a Solution


Tried using h = v(i) * t - 1/2at^2 to find the initial velocity (with h as 3).
Unsure exactly of where I should be headed...

*SOLVED*
 
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Using h = vt - 1/2at^2, I've gotten the quadratic (-4.9t^2 + 9.249t + 3). From there, to determine the velocity (magnitude), I isolated the portion of the parabola between y = 3 (x = 1.888) and y = 0 (x = 2.17). I'm just unsure of how to find the time with the diver starting 3 meters above the water.
 
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