Physics
posted by Joel .
if a ball is thrown straight upward and is caught 5s after being thrown,how fast must it have been going when it left the person s hand?help

Hint: It takes the same amount of time to go up, as it does down, so use 2.5 as t. And your only acceleration will be gravity acting downwards.
Figure out a, and vi, then put them into one of your kinetic formulas and you should get your answer. 
A ball is thrown vertically into the air and takes 5s to return to the thrower, from time of projection. What is the time it takes to reach maximum height ?