Why The Street Light is Yellow
Street Lamps Street lights are bright yellow in color most of places, the reason behind this is the type of lamps used in streets, Sodium Vapour Lamps How Sodium Vapour Lamps work Sodium Vapour lamps are made of a glass tube filled with inert gas like helium and argon and a small amount of sodium. Two electrodes are placed on the ends of the tube. When a voltage is applied across the electrodes, the inert gas inside the tube ionizes and current starts flowing through it. It creates a pinkish red glow. Because of the flow of current the temperature increases and this caused the sodium to vaporise. The sodium vapor then stabilizes the electric arc and sodium vapor creates a monochromatic yellow light. Advantages & Use Human eyes can detect light from wavelength 390 - 700 nm , and sodium vapor generates light of around 600nm wavelength which is quite useful zone of visibility. That means most of the energy coming out this lamps is in the form of visible light...