A child in a boat throws a 5.90-kg package out horizontally with a speed of 10.0 m/s. The mass of the child is 26.6 kg and the mass of the boat is 38.2 kg . Calculate the velocity of the boat immediately after, assuming it was initially at rest.
Assume there is no external force act in the system. Take the direction of package is positive. m1u1 +m2u2 =m1v1 + m2v2 0+0=(26.6+38.2)v + (5.9)(10) v= -0.910 m/s