How might you distinguish a sodium vapor street lamp from a mercury vapor steet lamp?
http://en.wikipedia.org/wiki/Sodium_lamp
http://en.wikipedia.org/wiki/Mercury-vapor_lamp
I think you would see colors better with the Mercury Vapor Light
You can distguish them by the color.
Low pressure sodium lamps (now seldom used for lighting) are bright yellow. High pressure sodium lamps are a warm pink-white (because the yellow sodium lines become broadened and Na2 forms).
Mercury vapor lamps are white with a bluish to violet tint.
To distinguish a sodium vapor street lamp from a mercury vapor street lamp, you can observe the color of the light emitted by the lamp. Sodium vapor lamps produce a bright yellow light, while mercury vapor lamps produce a white light with a bluish to violet tint.
Sodium vapor lamps can be further categorized into low-pressure sodium lamps and high-pressure sodium lamps. Low-pressure sodium lamps emit a bright yellow color that is more saturated, while high-pressure sodium lamps emit a warm pink-white color due to the broadening of the yellow sodium lines and the formation of Na2.
To identify the type of lamp, you can visually observe the color of the light emitted by the lamp. If the light appears bright yellow, it is likely a sodium vapor lamp. If the light appears white with a bluish to violet tint, it is likely a mercury vapor lamp.