1. The problem statement, all variables and given/known data You throw a ball vertically upward from the roof of a tall building. The ball leaves your hand at a point even with the roof railing with an upward speed of 15.0 m/s; the ball is then in free fall. On its way back down, it just misses the railing. Find (a) the position and velocity of the ball 1.0 s and 4.0 s after leaving your hand; (b) the velocity when the ball is 5.0 m above the railing; (b.1) How long will the ball reach 5 m (c) the maximum height reached and the time at which it is reached; and (d) the acceleration of the ball when it is at its maximum height. 2. Relevant equations Freefall equation like Vf=Vo-gt and etc 3. The attempt at a solution T at 1 a.) ΔY = (15 m/s)(1 s) - (1/2)(9.8 m/s^2)(1 s)^2 ΔY = 10.1 m T at 4 ΔY = -18.4 m V at 1 Vf = (15 m/s) - (9.8 m/s^2)(1) = 5.2 m/s V at 4 Vf = -24.2 m/s b.) Vf^2 = Vi^2 - 2gΔy Vf^2 = (15 m/s)^2 - (2)(9.8 m/s^2)(5 m) Vf^2 = 11.27 m/s b.1) (11.27 m/s) = (15 m/s) - (9.8^2)(t) t = 0.38 5 m = (15 m/s)(t) - (1/2)(9.8 m/s^2)(t) t = 2.68 I'm a bit confuse here I got 2 different answer in this part. Really need a big help here c.) a = Δv/Δt -> t = Δv/a -> t = (15 m/s)/(9.8 m/s^2) tmax = 1.5306 Δymax = (15 m/s)(1.5306 s) - (1/2)(9.8 m/s^2)(1.5306 s)^2 y = 11.48 d.) The answer is -9.8 m/s^2 right? Constant?