Starting at rest, two students stand on 20-kg sleds, which point away from each other on ice, and they pass a 10-kg medicine ball back and forth. The student on the left has a mass of 57 kg and can throw the ball with a relative speed of 15 m/s. The student on the right has a mass of 44 kg and can throw the ball with a relative speed of 11 m/s. (Assume there is no friction between the ice and the sleds and no air resistance.)
(a) If the student on the left throws the ball horizontally to the student on the right, how fast is the student on the left moving immediately after the throw?
(b) How fast is the student on the right moving right after catching the ball?
(c) If the student on the right passes the ball back, how fast will the student on the left be moving after catching the pass from the student on the right?
(d) How fast is the student on the right moving after the pass?