Christmas lights, like LEDs, emit individual colors of light. However, all other physical properties of Christmas lights are similar to incandescent lamps. Incandescent lamps typically emit "white" light, but can produce individual colors of light when a colored filter or coating is used. Christmas lights are examples of tiny, incandescent lamps that produce color due to colored coating found on the glass surrounding the tungsten filament. LEDs, unlike Christmas lights, emit various colors of light not as a result of the filament and a colored filter, but as a result of a different process that we will learn more about in future activities.
Traffic lights emit their characteristic red, yellow, or green light. Based on your observations and what you have learned, can you determine if traffic lights are incandescent lamps or LEDs? If yes, explain how. If not, describe an experiment that could make the determination (even if you cannot do the experiment).