How often do you want to get close to the car ahead? Close enough to be able to see what's on the parcel tray? If the answer is always, often or even once in a while, you're in danger of running into the back of the car in front. You are in serious need of reviewing how you drive rather than blame the driver in front for stopping suddenly in case you do run into his back, which you will sooner or later.
You see, no matter how good the brakes are, in most cars you must fi rst apply them to get the car to stop. This means braking is heavily dependent on your reaction time, and the average human reaction time is about 1.5 seconds, which is plenty of time for a crash to happen. So the simple rule of thumb is the closer you are to the car ahead the less your reaction time needs to be. Now, think again, are your reactions fast enough for you to apply the brakes and get the car to stop before you run into the back of the car whose parcel tray you can see? Unlikely.
At the same time it isn't practical to suggest that you keep as large a gap as possible with the car in front. But, as with all things, there's a solution. Drive at such a distance where you're not getting left behind but you can still stop well in time in an emergency. How do you do that? Here's how.
Follow the three-second rule. It's a simple rule really. It simply means that your car should pass a point at least three seconds after the car ahead has crossed the same point.
First, identify a fixed point along the road, like a lamp post. Let the car ahead pass this point (in this case the lamp post). Now you ensure that you're able to count slowly from 1 to 3 before your car crosses the same lamp post. Now, maintain this gap.
A three second gap between your car and the one in front will give you enough time to react to any emergency manoeuvres that the driver in front might need to make. At the same time you won't be left behind.
But remember that stopping distances also depend on factors like the surface condition. So, if it's raining and the sufrace is wet, or there's an oil spill on the road for instance, the time required to stop increases and with it the 3 second rule.
The distances shown are a general guide and could vary depending upon your thinking distance, road surface, weather conditions and also the condition of your car