Final answer:
Switch to low beams when an oncoming vehicle is within 500 feet and when following a vehicle, switch within 300 feet to ensure safety. This is important to avoid blinding the other driver with your headlights and causing a potential hazard on the road. By using low beams, you ensure that the light from your headlights is directed downward and does not interfere with the visibility of the oncoming vehicle.
Step-by-step explanation:
When driving with high beams on, you must switch to low beams when an oncoming vehicle is within 500 feet. This is to prevent the blinding glare from your headlights from impairing the other driver's vision and creating a hazardous situation. For drivers following another vehicle, the rule is to switch to low beams when you are within 300 feet of the vehicle in front of you. It's important to know and follow these distances to ensure road safety for all users.