2006-10-18 01:50:31 · 17 answers · asked by ? 1 in Politics & Government ➔ Law Enforcement & Police
yellow (sodium) streetlight provide the best visibility while manitaining your night vision. They give less noticable glare.
They do not help with light pollution, although all streetlights are positioned so that they do not directly shine upwards
2006-10-18 01:56:22 · answer #1 · answered by Vinni and beer 7 · 2⤊ 0⤋
Low pressure sodium vapour (in the bulbs) conducts electricity, but doesn't need much current to glow. A white glow from a hot metal filament or a standard fluorescent tube needs more power. It is much cheaper to run sodium vapour streetlamps, but the glow is orange. Passing a current through the gas gives the electrons orbiting each sodium atomic nucleus more energy. That energy is released in exactly the same amount (as orange light) by the electrons as they drop back to a lower orbit (Quantum physics).
2006-10-18 02:00:43 · answer #2 · answered by Blunt Bloke 1 · 2⤊ 0⤋
This is because we get lots of fog and mist, especially during the period September through March. The orange lamps penetrate the fog whereas white light is not as efficient. These orange lamps first made their entry in London during the smogs of the 1950s.
2006-10-18 01:57:42 · answer #3 · answered by Anonymous · 1⤊ 0⤋
Because they are sodium based lights instead of mercury. The sodium lights cut fog better due to the amber hue and they run on less energy
2006-10-18 01:58:40 · answer #4 · answered by OccamsTheory 2 · 1⤊ 0⤋
I've been whinging about those lights for years and it seems the Council's got to hear about it at last as they've started changing to a sort of off cream colour where i live.
2006-10-18 09:23:16 · answer #5 · answered by greg m 3 · 0⤊ 0⤋
white is a very bright colour and so produces glare, especially in wet weather, a good example of this is headlights on peoples cars, have you ever been blinded by oncoming traffic, this is what would happen if all the lights were white!
2006-10-18 02:00:02 · answer #6 · answered by ♥Lexi♥ 3 · 0⤊ 0⤋
Its easier to see orange lights in dense fog than white lights.
2006-10-18 02:00:15 · answer #7 · answered by Presea 4 · 1⤊ 1⤋
I gather that its to do with safety, as when its foggy white light spreads more and visability is far less.
2006-10-18 03:14:16 · answer #8 · answered by Joolz of Salopia 5 · 1⤊ 0⤋
Because they are sodium lights, supposed to give more light for less electricity
2006-10-18 01:59:35 · answer #9 · answered by Anonymous · 2⤊ 0⤋
Cause the Unionists wrote it into the Good Friday accord?
2006-10-18 01:56:46 · answer #10 · answered by knoWall 4 · 0⤊ 2⤋