Question

A diver with a mass of 80.0 kg jumps from a dock into a 130.0 kg boat at rest on the west side of the dock. if the velocity of the diver in the air is 4.10 m/s to the west, what is the final velocity of the diver after landing in the boat?

Answer 1

Applying conservation of momentum;

$m_{1} v_{1} + m_{2} v_{2} = m_{f} v_{f}$

Where m1 = 80.0 kg; v1 =4.10 m/s; m2 = 130.0 kg; v2 = 0; mf = (80+130) kg; vf = ??

Therefore,
80*4.1 + 130*0 = 210*vf
vf = (80*4.1)/210 = 1.56 m/s