1. The problem statement, all variables and given/known data A ball is thrown upwards from a point near the sidewalk next to a tall office building. At some later time an occupant of the building, exactly 5.1 meters above the point from which the ball was released, sees it pass her window with a speed of 2.9 m/s. Calculate the maximum height reached by the ball. You may neglect air resistance. Take the acceleration due to gravity to be 9.82 m/s^2 2. Relevant equations Kinematic Equations y = Vot + (1/2)at2 Vf = Vo + at Vf2 = Vo2 + 2ay y = t * [ (Vo + Vf) / 2 ] 3. The attempt at a solution Using Kinematic equation Vf^2=Vo^2+2ay I solve for Vo (2.9)^2=Vo^2 - 19.64*5.1 Vo = 10.01 m/s To find max height I set Vf to 0 and solve for y using the same acceleration and the newly found Vo. 0 = 10.01^2 - 19.64y y=5.1 m Obviously this doesn't work since 5.1m is where the person at the window sees the ball traveling with velocity. Any help would be great, I tried using the other kinematic equations but it got too messy too quickly.