Dover+Lab+12+-+Physlets

Illustration 8.1
As the time that the force has to act on the the object increases, the momentum (and velocity) of the object increases. Momentum is not independent of the mass. When the mass increases the velocity of the cart decreases.

Illustration 8.2
When the mass of the cart increases, the work decreases. The longer time a force is applied to an obejct the greator the momentum and kinetic energy the object has.

Illustration 8.3
"Hard" objects, when colliding, have a fast jerk over a short distance and "soft" objects, when colliding, have a slow jerk over a long distance.