How is light emitted from incandescent lamps? Fluorescent lamps? Candles?

1 answer

incandescent ... the filament is heated by the current flowing through it , causing it to glow ; like in a toaster oven

fluorescent ... the inside of the tube is coated with a material that fluoresces under ultraviolet light ... there is metal that is vaporized by the current through the tube ... the metal emits the UV light

candle ... heat from the oxidation (burning) of the wax , raises carbon atoms to higher energy states ; the atoms emit photons (light) as they return to a lower energy level