Final answer:
Drivers should use the three-second rule as a guideline for a safe following distance under ideal conditions, which increases with higher speeds and poor conditions.
Step-by-step explanation:
When following other motorists, drivers should maintain a safe following distance that allows them enough time to react and stop if necessary. A common guideline is the three-second rule, which states that a driver should stay at least three seconds behind the vehicle in front during ideal road and weather conditions.
For a car traveling at 60 km/hr (the speed mentioned for towns and cities) and considering an average car length of 3.5 meters, a safe following distance of 4 to 5 car lengths, or 14 to 17.5 meters, would be appropriate as a minimum to ensure safety.
Moreover, when considering the braking distance and driver reaction time, as well as factors like road conditions, it becomes clear that following this rule helps account for the total distance a vehicle travels from the moment the driver perceives a hazard until the vehicle can come to a full stop.