Final answer:
You should use low beams within 500 feet of an oncoming vehicle at night. The inverse square law shows that light intensity decreases quickly with distance, making low beams necessary for safety in various visibility conditions.
Step-by-step explanation:
You should use low beams whenever you are within 500 feet of an oncoming vehicle at night to avoid blinding the other driver.
It is crucial to switch from high beams to low beams not just for courtesy, but also for safety reasons. In conditions of poor visibility, such as fog or heavy rain, it is also recommended to use low beams as high beams can cause glare and decrease visibility even further.
In relation to the intensity and distance of light, the inverse square law explains that the illuminance from a light source diminishes rapidly as you move away from it. Therefore, at greater distances, headlights will appear significantly dimmer, requiring the use of high beams to see further ahead while driving at night, provided there is no oncoming traffic.
You should use low beams whenever you are within 500 feet of an oncoming vehicle at night. The purpose of using low beams is to prevent blinding the driver of the oncoming vehicle by reducing the glare. Low beams have a range of around 150-200 feet, which is sufficient for illuminating the road ahead without causing discomfort to other drivers.