500'
Be considerate in using your high beams. Your headlights must be on low beam when you are within 500 feet (150 m) of an approaching vehicle, or within 200 feet (60 m) of a vehicle ahead of you, even if the vehicle ahead is in a different lane. You should also dim your lights for pedestrians approaching you. http://www.nydmv.state.ny.us/dmanual/chapter10-manual.htm (Alaska and Oregon are the same as New York - 500 feet.)
300 feet
300 feet
Those laws vary from place to place. Common courtesy dictates to dim your lights well before they reach the oncoming vehicle.
at least 2m
In most states it is 500 Feet. Common sense should prevail.
If you can see his headlights, drop your high beams. In some states its the law 300 feet at least.
At night a driver should dim his headlights when an oncoming motor vehicle comes within 1,000 feet. You should switch your headlights from full beam to dipped beam when a oncoming car passes. It is unsafe to leave your headlights on full beam as it blinds the driver of the oncoming car.
At night a driver should dim his headlights when an oncoming motor vehicle comes within 1,000 feet. You should switch your headlights from full beam to dipped beam when a oncoming car passes. It is unsafe to leave your headlights on full beam as it blinds the driver of the oncoming car.
300
Railroad tracks, tunnels, or intersections.