Abatter hits a pop-up straight up over home plate at an initial velocity of 15 m/s. the ball is caught by the catcher at the same height that it was hit. at what velocity does the ball land in the catcher's mitt?

15 m/s

Explanation:

Ignore air resistance. According to the law of energy conservation, the total potential kinetic energy of the object remains the same if there's no energy loss. Since the catcher catches the ball at the same height that it was hit, the potential energy is the same. Therefore the ball kinetic energy should remain the same, and so does its velocity.

power out to power in less than 100%

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.