9. An 8,0 kg ball travelling at 4 m/s collides head on with a 3 kg ball
travelling at 14 m/s. The balls bounce off each other and travel
back the way they came. The 8.0 kg ball travels away at
2 m/s. Calculate: a) the velocity of the 3 kg ball after the collision
b) the kinetic energy before and after the collision. c) State whether or not the collision is elastic and explain your
answer.
