Originally Posted by **songoku** Hi spanky
1) 40 = Vo t + 1/2 g t^2
2) Consider the first ball to find t in term of Vo. There are 2 cases, when the ball is thrown up and when the ball falls to the ground. Find the tiime taken for the 2 cases and add them to find t in term of Vo.
3) Subs. (2) to (1) and solve for Vo. You'll get nasty equation but I think you still can get Vo |

ive tried both but i cant seem to get it. also i forgot to mention the answer it is Vo=4 m/s, but i dont know how to get the answer ive tried it all seems quite hard without time nor iniitial velocity.

thanks for ur help though.