Utah CDL General Knowledge Practice Test

Keeping your speed slow enough to stop within your headlight range is a fundamental safety practice when driving at night. Headlights illuminate only a limited distance ahead, typically between 100 to 200 feet, depending on the type of light used and the vehicle. Because visibility is reduced at night, it's crucial that a driver maintains a speed that allows them to stop safely within the distance that they can see.

This practice gives you adequate time to react to unexpected hazards such as animals, pedestrians, or road debris that may appear suddenly within your field of vision. If you're driving too fast, the distance covered in the time it takes to perceive a hazard and react may exceed what your headlights can illuminate, significantly increasing the risk of an accident. Thus, adjusting your speed to stay within your visible range enhances safety for you and others on the roadway.

The other choices do not promote safe night driving. For instance, avoiding high beams can reduce visibility when lighting conditions are particularly poor, and using only parking lights limits your visibility significantly. Driving as fast as you can without consideration of your headlight range is inherently dangerous, as it compromises your ability to respond effectively to road conditions and obstacles.