Various Lighting Devices and How they work
In the night we use artificial lights. For this purpose we use different types of devices like Bulbs, Tubes, CFLs, LEDs and so many others. Thought their basic idea is same, converting electrical energy into light energy, these devices achieve this goal using different techniques. Lets have a basic idea how they work. Light Bulbs or Incandescent Bulbs As the name says, Incandescent, "emitting light because of being heated" the basic idea of getting light by heating a resistance. Jule's law says when electric current flows through a conductor it gets heated. The amount of heat will mainly depend upon the current, time of flow and the resistance of the conductor. So more the resistance more the heat. Thats the reason a high resistance thin wire of tungsten is used as a filament. When current flows through the filament it turns red hot and emits light. The filament needs to be protected from getting oxidized and fused by the environment so it's protected ins...