A batter hits a pop-up straight up over home plate at an initial velocity of 29 m/s. The ball is caught by the catcher at the same height that it was hit. At what velocity will the ball land in the catcher's mitt?

Question

A batter hits a pop-up straight up over home plate at an initial velocity of 29 m/s. The ball is caught by the catcher at the same height that it was hit. At what velocity will the ball land in the catcher's mitt? 
none of these 
29 m/s     
14.5 m/s 
-14.5 m/s 
-29 m/s

drwls · Answer

-29. Total energy is conserved so the kinetic energy (and v^2) when caught must be the same as when the ball was hit. However, the direction of the velocity changes from up to down.