• Question: how does the light bulb work

    Asked by bigballs2 to Sheila, Piyush, Natalia, Gary, Dimitar on 9 Nov 2018.
    • Photo: Gary Munnelly

      Gary Munnelly answered on 9 Nov 2018:

      Light bulbs work by passing an electrical current through a filament made of a metal called tungsten. The filament heats up and begins to glow very brightly emitting light. Now, here’s the really interesting part. If a light bulb was full of air the filament would actually burn, breaking the circuit and blowing the bulb. So light bulbs are actually full of a gas called Argon which stops the tungsten filament from deteriorating too quickly. Of course, the tungsten will still degrade, just more slowly in this environment. So eventually the bulb wears out and you need to buy a new one.

    • Photo: Dimitar Shterionov

      Dimitar Shterionov answered on 11 Nov 2018:

      Reading through Gary’s response I don’t think I can add anything extra. Thumbs up Gary đŸ™‚

      Maybe I will add something about Light Emitting Diodes (or LED in short) lights.

      So, as Gary said light bulbs work with when electricity heads up tungsten (also called woflram). However, they use a lot of electricity and burn out quickly. LEDs on the other hand are much more energy efficient and more resilient. LEDs are made of two types of semiconductors – one that is positively charged and another that is negatively charged. They allow electricity to flow in only one direction and are very useful in all types of electric circuits. In addition, when electricity flows photons are emitted thus creating light. Depending on the material and the current the light can vary. It can be for example more white or more yellow, but also can be infrared – not visible for the human eye. An LED light bulb would contain several LEDs.

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