Final answer:
The statement that you should never brake when your vehicle is skidding is false, especially with ABS-equipped vehicles. Skid mark analysis can reveal information about the car's speed. Easing off the brake before stopping takes advantage of static friction for a smoother stop.
Step-by-step explanation:
Regarding the question of whether you should never brake when your vehicle is skidding, the answer is false. Modern vehicles are equipped with anti-lock braking systems (ABS) that allow you to brake while steering to avoid a skid. However, if your vehicle does not have ABS, traditional advice was to steer into the skid and avoid braking abruptly to regain control of the vehicle.
In regards to the friction between tires and the road, the coefficient of friction plays a crucial role in determining braking distance. In the scenario where a car leaves a skid mark of 30.5 meters before stopping, a trained expert such as a police officer or accident reconstructionist can determine if the car was speeding based on the length of the skid marks and the known coefficient of friction. Therefore, if you are confident that you were not exceeding the speed limit despite the skid marks, it could be worth discussing the circumstances with legal counsel to consider fighting the ticket in court.
Concerning static and kinetic friction, learning to let up slightly on the brake pedal as you come to a stop is related to the transition from kinetic friction to static friction (which holds the car stationary smoothly). By easing the brake pedal slightly before stopping, you are taking advantage of the maximum threshold of static friction just before the car comes to a rest, thereby achieving a smoother stop.