| A | B |
| momentum | mass times velocity |
| inertia in motion | momentum |
| impulse | force times time |
| change in momentum | impulse |
| law of conservation of momentum | changes internal to a system, momentum must remain the same |
| elastic collision | collision with no heat or deformation |
| inelastic collision | collision with heat or deformation produced |
| colliding objects bounce perfectly | elastic collision |
| colliding objects become entangled | inelastic collision |
| net momentum 1 = net momentum 2 | law of conservation of momentum |