Question

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.

Answer 1

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