A piece of modeling clay is motionless in space. Another piece of clay that is 4 times as massive moving at 10m/s collides with it and sticks to it. What is the momentum of the combined blob after the collision?

Answer 1

Linear momentum is conserved.

If the mass of the motionless clay piece is m, that of the other piece is 4m. The heavier piece initially has all of the momentum.

4m*10 m/s = (4m + m)*Vfinal
Vfinal = (4/5)*10 = 8 m/s