While driving at 40 mph, you see a red stop light ahead. You press your brakes for several seconds, gradually coming to a stop. A little later on the same road at 40 mph, you approach another light, this time green. While approaching this light, it suddenly changes to yellow. You make a split-second decision to put on your brakes to avoid going through a red light. With the brakes applied quite hard, you quickly stop, waking up your sleeping friend in the front passenger seat.