Copper Coil in Table Lamp: Understanding Its Purpose and When to Use an Adapter

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The copper coiled sheets of steel in the table lamp function as a ballast, which is an inductor that regulates current and provides the necessary voltage to light the fluorescent lamp. The ballast generates a high voltage when the lamp is initially turned on, allowing it to draw current and illuminate. After lighting, it limits the current to prevent overheating. An adapter is needed when a device requires a different voltage than the mains supply or needs a direct current (DC) supply, typically at a lower voltage. Understanding these components is essential for proper lamp functionality and safety.
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In my table lamp, there is only a switch, and a copper coiled sheets of steel. I am in K9 and would like to know what are those sheets for ?

My second very fundamental question is when should we use an adapter ?

Thank you
 
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copper coiled sheets of steel

Sounds like you have a fluorescent table lamp.

You might like to read about these here:
http://en.wikipedia.org/wiki/Fluorescent_lamp

The "copper coiled sheets of steel" thing is called a ballast and it is a type of inductor.

A current is passed through this and then switched off. This is done by the "starter" which looks like a small plastic cylinder.
This generates a large voltage from the ballast, which makes the lamp draw current and light up.
After that, the current in the lamp is limited by the inductance of the ballast so that the lamp does not get too hot.
So, the ballast performs two functions.

You use an adaptor when the device you want to power uses a different voltage to the mains supply or when the device needs a DC (direct current) supply.
Usually the DC supply will also be at a lower voltage than the the mains supply as well as DC.
 
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