[SOLVED] Challenging problem (free fall) I am stuck with couple of problems and i keep getting the wrong answer. Perhaps my approach is wrong. Below are the questions and they way i approached the problems. A basketball player grabbing a rebound jumps 80 cm vertically. (a) How much (total) time does the player spend in the top 25 cm of this jump? (b) How much (total) time does the player spend in the bottom 25 cm of this jump? Ok so here is what i did. I took Vf=0 at the top. Vo= unknown, a = -9.8, Y = .25m so i used the formula Y= ((vf^2 - Vo) / 2a) And i got Vo = 2.21ms Now I used Vo in the equation Y = (vf+Vo)t To find out T= .22s now the time going up is equal the time coming down which is 2t = .45s But it tells me that my answer is wrong.And how should i approach the problem (b)??? ------------------------------------------------------- A lead ball is dropped into a lake from a diving board 5.06 m above the water. It hits the water with a certain velocity and then sinks to the bottom with this same constant velocity. It reaches the bottom 4.92 s after it is dropped. (Assume the positive direction is upward.) (a) How deep is the lake? (b) What is the average velocity of the ball? (c) Suppose that all the water is drained from the lake. The ball is now thrown from the diving board so that it again reaches the bottom in 4.92 s. What is the initial velocity of the ball? (a)I put the problem in two parts. When the ball is dropped and it hits the surface of water then Y = -5.06m, a= -9.8 and Vo = 0 at the top. Then using Y = (vf^2 - Vo^2) / 2a i got Vf = 9.95, then i used that to find out the time and i got t = 1.01s Now the total time given is 4.9 so now the time it took for the ball from the surface of the water to the bottom would be 4.9 -1.01 = 3.89s Now i solved for Y (depth of the lake) t= 3.89, Vo = 9.95 and Y = ? by using Y = 1/2(Vf+Vo)t and it is Y = 19.35 and it still says i am wrong please help.