Final answer:
To avoid tailgating and the possibility of a rear-end collision, the recommended following distance under normal driving conditions is three seconds, known as the "three-second rule."
Step-by-step explanation:
To avoid tailgating and to help prevent a rear-end collision, it is recommended to keep a safe following distance between your car and the vehicle in front. This safe distance is often referred to as the "three-second rule." This rule suggests that you should stay at least three seconds behind the vehicle in front of you under normal driving conditions. To gauge this, you can pick a stationary object on the side of the road, such as a signpost or a tree, and note when the car in front of you passes it. You should not pass the same object before you can count to three seconds.
However, in adverse conditions like wet or icy roads, or when following large vehicles which block your view ahead, it may be safer to increase this gap to four or even five seconds to allow for the greater stopping distance required. Tailgating, or following too closely, increases the risk of a rear-end collision significantly, especially if the vehicle in front has to stop suddenly. The stopping distance is affected by several factors such as road conditions, driver reaction time, and the vehicle’s braking capabilities.
The distance necessary to stop a car depends greatly on these conditions, and therefore, maintaining an adequate following distance is crucial for safety on the roads.