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how does electricity flow into a bulb in a table lamp

Posted by emkdavis on 8 months ago


Considering the law of energy conservation, it can be said that what a light bulb does not produce light and needs electricity to do that, but rather converts electric energy into light energy. In other words, the energy simply changes its form. The main question is, “how?”

To find the answer, let’s take a look at what a light bulb is. It is, actually, a glass bubble (surprise!) with two terminals inside of it - positive and negative. Between these two terminals, a tungsten element is located, connecting them. When you turn on the lamp, electricity from the power socket “flows” into the bubble; the flow of electrons supplied to both of the terminals heats up the tungsten element between them. As things heat up, they start emitting light, and it’s tungsten’s physical property to start glowing after a very short period of the “electron bombing.”

The light bulb is not empty inside - it’s filled with inert gas, which helps to prevent overheating. If the tungsten wire tears apart, electricity cannot pass the full loop, so to say, and the bulb won’t work.

Answered by Keith Chadwick  on Oct 10, 2016
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