일반물리학 1 — Center of Mass and Linear Momentum: Problem 42

42 A 15.0 kg package is moving at a speed of 10.0 m/s vertically upward along a y axis when it explodes into three fragments: a 2.00 kg fragment is shot upward with an initial speed of 20.0 m/s and a 3.00 kg fragment is shot in the positive direction of a horizontal x axis with an initial speed of 5.00 m/s. Find (a) the speed of the third fragment right after the explosion and (b) the total kinetic energy provided by the explosion.