When your at a light and it's red is it true you have to go over a certain line to trigger the color change or is it on a cycle that does it automatically?
2007-01-29 09:18:36 · 6 answers · asked by Anonymous in Cars & Transportation ➔ Commuting
Some lights are set up on a timer. i.e. 30 seconds one way, 1:30 another. These can get complex, too, and can operate on different timers on different days or different times of day.
Others have a series of sensors which can detect where cars are, and if there are at least a certain amount, if not more. IF you look carefully, you can see cuts in the road material (usually in a hexagon or octagon) where the road was removed, the sensor installed, and then resurfaced. Sensors and timers often work in tandem with timed lights switching when the sensors detect a certain amount of cars in line.
Last, some are controlled by people.
There are also devices (which only police, ambulances, and firetrucks can legally have) that flash lights at a certain speed in a certain arragement with a certain brightness and a certain pattern that will cause lights to change and give them the right-of-way. But only newer traffic lights respond to these.
2007-01-29 09:30:19 · answer #1 · answered by wax 3 · 89⤊ 5⤋
Traffic Lights How They Work
2016-12-10 18:15:55 · answer #2 · answered by sechler 4 · 0⤊ 0⤋
This Site Might Help You.
RE:
Traffic Lights...HOw do they work?
When your at a light and it's red is it true you have to go over a certain line to trigger the color change or is it on a cycle that does it automatically?
2015-08-18 14:37:33 · answer #3 · answered by Karlis 1 · 0⤊ 0⤋
many lights are on a timed cycle. some though are controlled by either humans in a control center for heavy traffic periods or by computer when traffic is backing up in one area or another.
2007-01-29 09:22:11 · answer #4 · answered by Anonymous · 6⤊ 5⤋
wolfgang gartner deadmau5 infected mushroom i could give you 1000 but you asked for techno/trance so here you go
2016-03-22 14:25:23 · answer #5 · answered by ? 4 · 0⤊ 0⤋
some are set up with a sensor so that when u drive over it, it will change...others are just set on a timer
2007-01-29 09:22:18 · answer #6 · answered by Anonymous · 8⤊ 2⤋
some residential street lights have sensors on the street but if you want them to change quicker flash your high-beams at it and they change in a snap...police cars use there flashing lights for that...just dont let one see you do that. hehe
2007-01-29 09:29:53 · answer #7 · answered by damian_guy 1 · 6⤊ 8⤋
Usually they have a sensor.
2007-01-29 09:23:52 · answer #8 · answered by Cecilia ♡ 6 · 4⤊ 6⤋
its on a timer..
2007-01-30 16:02:49 · answer #9 · answered by Anonymous · 4⤊ 5⤋