An incandescent bulb has a few basic parts.įirst, there's the bulb that you're used to seeing.

We'll look at what the filament is made of in the next section.Incandescent light bulbs have been around for many decades and are still used in the majority of homes around the world. In the next section, we'll find out why this is, and we'll examine the role of the glass bulb and inert gas.

Tungsten is used in nearly all incandescent light bulbs because it is an ideal filament material. In a 60-watt bulb, the coil is less than an inch long. That is, the filament is wound up to make one coil, and then this coil is wound to make a larger coil. The tungsten is arranged in a double coil in order to fit it all in a small space.

In a typical 60-watt bulb, the tungsten filament is about 6.5 feet (2 meters) long but only one-hundredth of an inch thick. The filament in a light bulb is made of a long, incredibly thin length of tungsten metal. But if they are heated to a high enough level - around 4,000 degrees Fahrenheit (2,200 degrees C) in the case of a light bulb - they will emit a good deal of visible light. Metal atoms release mostly infrared light photons, which are invisible to the human eye. When they fall back to their normal levels, the electrons release the extra energy in the form of photons. A thinner conductor heats up more easily than a thicker conductor because it is more resistant to the movement of electrons.īound electrons in the vibrating atoms may be boosted temporarily to a higher energy level. The energy of each impact vibrates an atom - in other words, the current heats the atoms up. As the electrons zip along through the filament, they are constantly bumping into the atoms that make up the filament.

How does the light bulb work