An entertainer juggles balls while doing other activities. In one act, she throws a ball vertically upward, and while it is in the air, she runs to and from a table 5.50m away at a constant speed of 2.50m/s, returning just in time to catch the falling ball. (a)With what minimum initial speed must she throw the ball upward to accomplish this feat? (b)How high above its initial position is the ball just as she reaches the table?

3 answers

i know just v1=25.7

bat the secound part i don't know about it ..
What you are proably doing wrong is that you a taking the Dis[lacement as it comes.Be careful because the ball could be on its way back down. i wont do the question out but you have to find it max heigth by entering the final velocity as 0 and then subtract this answer for the one you got for the displacement
Also be careful of sign if the ball is going up the acceleration is -9.81