Here's the question: A safe following distance for a car is often described as "two seconds". In other words, if you pass the same point as the car in front of you two seconds later, the distance between the cars is safe. Inquiry: is this rule true at highway speeds? Parameters: Car A is in front, car B is behind. Both are traveling with the same velocity (approx 100 km/h). There are two seconds between car A and car B. Car A will commence braking at a rate you will be given later. Car B will not react for a certain amount of time (given later) and then will brake. The rate of car B's braking will be given later. Question: Can car B stop before it collides with car A? I was given the question this way. It's basically an evaluation that my teacher will give on a day and I have time to prepare for it. What would be reasonable amounts for the parameters? My thoughts: It basically depends on the rate of the braking of the cars. But in general, the car's deceleration will be approximately same and since we can take that the car B driver will react quickly than 2 sec therefore they may not collide but they really depend on the rates, which is why I was wondering, what would be a reasonable breaking rate? and how would I unput that into a formula? Thank you very much.