1. A pitcher throws a baseball with mass 0.2 kg straight upward with an initial speed of 20.0 m/s. (a) How much work (in J) has gravity done on the baseball when it reaches a height of 15.0 m above the pitcher’s hand? Note: Consider the direction of the gravity. (b) Calculate the speed (in m/s) of the baseball at a height of 15.0 m above the pitcher’s hand.

1. A pitcher throws a baseball with mass 0.2 kg straight upward with an initial speed of 20.0 m/s. (a) How much work (in J) has gravity done on the baseball when it reaches a height of 15.0 m above the pitcher’s hand? Note: Consider the direction of the gravity. (b) Calculate the speed (in m/s) of the baseball at a height of 15.0 m above the pitcher’s hand.