Driving 101 Test

Very few people know how long a yellow light lasts. Do you?

How long is the yellow light?

• The time to stop.
• Half the time to stop.

The Time to Stop - Explanation

The yellow light is not the time to stop. If you voted for this answer, you are wrong.

Half the Time to Stop - Explanation

The yellow light lasts half the time it takes you to stop your vehicle. The yellow time is actually the time to go, not stop. When the light turns yellow and you can no longer comfortably stop, the yellow lasts for the time it takes you to travel toward and into the intersection. In order to get to the intersection before the lights turns red, you must go the speed limit or faster. If you slow down under the speed limit, you risk running a red light. This is why we often choose to beat the light. It is built into the math that we must beat the light.

Who is "you" in the time it takes "you" to stop your vehicle?

A driver travelling on dry pavement approaching a simple intersection. The driver must react to a yellow light faster than the 50th percentile passenger sedan driver. If stopping, the driver must decelerate faster than 50th percentile passenger sedan. In other words, the yellow light excludes half the driving population, all commercial vehicles, and anyone who drives on an icy road.