At 45 mph with an 80-foot vehicle in good weather, what is the least amount of space you should keep in front of you?

At 45 mph with an 80-foot vehicle in good weather, what is the least amount of space you should keep in front of you?

• A. 9 seconds
• B. 6 seconds
• C. 12 seconds
• D. 3 seconds

Answer: (A)

This question tests how much space you should leave in front when driving a long vehicle at highway speed, using a time-based headway. The idea is that you want enough margin to react and to stop safely if the vehicle ahead slows or stops, and this margin must be larger for a long vehicle. With an 80-foot vehicle traveling at 45 mph in good weather, you need a substantial space cushion to account for your reaction time plus the braking distance, and you must also consider the length of the vehicle in front. Even when conditions are ideal, a shorter gap won’t give you enough time to react and decelerate without risk of catching up to the lead vehicle. Among the options, the safest choice is the one that provides the most headway, because more space means more time to respond and stop. In practice, that larger cushion is the responsible, safer rule when you’re handling a long vehicle at higher speeds in good weather.

This question tests how much space you should leave in front when driving a long vehicle at highway speed, using a time-based headway. The idea is that you want enough margin to react and to stop safely if the vehicle ahead slows or stops, and this margin must be larger for a long vehicle.

With an 80-foot vehicle traveling at 45 mph in good weather, you need a substantial space cushion to account for your reaction time plus the braking distance, and you must also consider the length of the vehicle in front. Even when conditions are ideal, a shorter gap won’t give you enough time to react and decelerate without risk of catching up to the lead vehicle.

Among the options, the safest choice is the one that provides the most headway, because more space means more time to respond and stop. In practice, that larger cushion is the responsible, safer rule when you’re handling a long vehicle at higher speeds in good weather.