Two cars move at a speed of 16 meters per second. Each of them has a passenger that is not wearing the seat-belt. Both of these cars decelerate abruptly. Car number one completely stops in 0.25 seconds. Car number two completely stops in two seconds. We know that in both cases, the passengers will continue moving after the car stops (due to their inertia). After the cars stop, passenger one and passenger two will be launched with the same speed? In other words, the time that the cars use to stop provokes different speeds in their occupants when launched due to inertia? I believe that time plays a role in determining the speed of the passengers when cars one and two stop. I am confused because the law of inertia tells that bodies continue moving at their same speed. But how can we explain that the passengers of a car that decelerates in 0.1 seconds end up crashing with the wind shield and that the passengers of a car that decelerates in ten seconds barely move in relation to the car? Thanks.