While driving you experience momentum as well as impulse. Momentum measures how hard it is to stop a moving object. You experience this when you are about to stop before a stoplight or a stop sign. Impulse is a sudden change and a change in momentum. The more momentum you have while driving the harder it is to stop. Momentum also depends the speed you are driving as well as the mass of the car. If you are driving and get into a collision the momentum stays the same from before and after the collision. Force is needed to change the cars momentum which is impulse because it changes the cars momentum over a period of time.