freely falling bodies

mandaa123

1. The problem statement, all variables and given/known data

A ball is thrown straight upward and rises to a maximum height of 18 m above its launch point. At what height above its launch point has the speed of the ball decreased to one-half of its initial value?

2. Relevant equations
i dont know.



3. The attempt at a solution
vi=0, d=18m, g=9.81, this is all i know.

LowlyPion

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