A ball is throw horizontally from the top of a building 35 m high. The ball strikes the ground at a point 80 m from the base of the building. Find the ball's initial velocity.(adsbygoogle = window.adsbygoogle || []).push({});

What I have done so far is to find the time it takes for the ball to reach the ground, using the x=V0t + 1/2 at^2 forumula, and I found the time to be 2.67 s.

Then I used that and plugged it into the Vf^2 = V0^2 + 2ax formula, and solved for a, finding it to be [-V0^2]/160

and then I plugged that into the x = V0t + (1/2) a t ^2 formula, and solved the quadratic equation, and found the initial velocity to be 60 m/s, but in my book it says that the answer is 30 m/s I just can't gigure out what I did wrong.

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# Homework Help: Kinematics problem

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