Occassionally, 2 black wires are placed across the road in a number of places along the road. They stay for a couple of weeks or so and are then removed. Do they count traffic or measure speed or something?
2007-10-30 08:33:53 · 25 answers · asked by jessica 1 in Cars & Transportation ➔ Safety
Yes, both.
They are used by various agencies to gather data on traffic patterns. It tells them how many cars use that stretch of road in a certain time period, and, by measuring the time difference between hitting each strip, how fast people tend to go on that road.
It is not unusual for the highway patrol to use them to figure out a good palce to put a speed trap.
2007-10-30 08:38:17 · answer #1 · answered by juicy_wishun 6 · 1⤊ 0⤋
Rick H - many a true word spoken in jest! They work on exactly the same principle, and measure the amount of traffic using the road (to be exact, they measure the number of axles that cross it).
Counting the number of axles doesn't give them the number of vehicles, because of course not all vehicles have the same number of axles. So they use two "wires". Obviously, that gives a much higher figure, but that doesn't matter - doubling the figure gives a more accurate result for comparison with other roads, and better takes into account the "different number of axles on different vehicles" problem.
All they need to know is that "x" number of clicks on the machine means "y" amount of traffic.
2007-10-30 21:01:15 · answer #2 · answered by Anonymous · 1⤊ 1⤋
It's like the chicken joke - why did 2 black wires cross the road?
Because ... (your answer goes here.)
Actually, I think they are pneumatic traffic counters. The weight of a vehicle compresses the air inside the tube (not a wire), which increments a counter in a box.
Back in the old day, a single tube did the trick. I'm not sure why 2 are needed today - perhaps to increase the accuracy.
2007-10-30 20:36:00 · answer #3 · answered by Tom-SJ 6 · 0⤊ 0⤋
They count traffic and measure speed of the cars as they pass. The data is usually used for upcoming construction projects to measure the impact on traffic.
2007-10-30 18:51:12 · answer #4 · answered by Matt R 2 · 0⤊ 0⤋
It counts the number of vehicles passing over them over a specific time period. This way county engineers can gauge the amount of traffic on that particular part of the road. It may lead to widening of the road, or the addition/modification of a traffic control device, like a red light, etc.
2007-10-30 15:39:39 · answer #5 · answered by johnson88 3 · 1⤊ 0⤋
Measure the speed along the road
2007-10-31 04:44:56 · answer #6 · answered by k 7 · 0⤊ 0⤋
They are used to count traffic travelling at a reasonable speed on that particular stretch of road.
2007-10-30 15:48:49 · answer #7 · answered by NIGEL T 1 · 0⤊ 1⤋
You are on the right track. I believe it is a traffic check. How many cars possibly travel the road.
2007-10-30 17:53:27 · answer #8 · answered by what u talkin' bout? 7 · 0⤊ 0⤋
It is traffic counting measure. Usually they do this to see how heavy the traffic is in certain areas
2007-10-30 15:36:56 · answer #9 · answered by ♥♥The Queen Has Spoken♥♥ 7 · 1⤊ 0⤋
They count the number of cars that pass. This is probably for the purpose of advertising fees. There are probably some billboards ahead, and if the owners of the billboards can demonstrate high traffic, then they can charge more for the advertising space, because more people will see the ad.
Make sense?
2007-10-30 15:38:17 · answer #10 · answered by Rick K 6 · 0⤊ 2⤋