Physics
posted by Lindsay .
A stone is thrown vertically upward. On its way up it passes point A with speed v, and point B, 12.6 m higher than A, with speed v/2. Calculate the maximum height reached by the stone above point B.
I am still stuck on this problem, mainly because I can't seem to get v/2. I think I know all the steps...but not having v/2 is keeping me from doing them.

well, you know the amount of kinetic energy lost from a to b, and the change in Potential energy
1/2 mv^1/2 m (v/2)^2= mg12.5
3/4 v^2=12.5*9.8
solve for v.