Keath+Physlets+8

8.1 Force represents a change in momentum. As mass changes, the momentum stays the same because the force will move it less resulting in a smaller velocity giving the same momentum. By applying a force over a longer period of time, the momentum becomes larger because Newton's definition of force is dp/dt (or change in momentum over change in time).

8.2 As the mass changes, the momentum and force stay the same, but the kenetic energy changes. The reason for this is that the larger mass is not moved as far as the smaller mass was due to the decrease in acceleration (ma=2m(1/2a)). The work changes massively due to the change in mass and thereofre the change in distance traveled.

8.3