In an emergency situation while driving one has tendency to jam the brakes, trying to stop in shortest distance. With wheels locked, the car slides and steering get useless. In ABS system the electronic sensors keep varying the brake pressure so as to keep the wheels rolling (without slipping) while ensuring that the friction remains limiting. Your friend has an old car with good brakes. He boasts saying that all the four wheels of his car get firmly locked and stop rotation immediately after the brakes are applied. You know that your new car which has a computerized anti lock braking system (ABS) is much safer. How will you convince your friend?
In a typical situation, car without ABS needs 20 m as minimum stopping distance. Under identical conditions, what minimum distance a car with ABS would need to stop? Coefficient of kinetic friction between tyre and road is `25%` less than the coefficient of static friction

Answer

15 m