Cathode facts for kids
A cathode is a special part of an electrical device called an electrode. It's like a path where tiny particles called electrons move. Electrodes are usually made of metal and help electricity flow.
Imagine electricity as a flow of charges. There are two ways to think about how it moves. One way is called "conventional current," which people used to think flowed from positive to negative. The other way is the "actual current," which is how electrons really move.
In simple terms, electrons go *into* the cathode. This lets an electric current go into devices like a battery or other electrical cell. Sometimes, electrons can even go into open space, like in an old cathode ray tube TV.
Contents
Cathodes in Different Devices
The cathode can act differently depending on the device it's in.
Batteries
In a battery, the cathode is the positive (+) side. Even though the battery gives off power, the electrons actually go *into* the positive terminal (the cathode) when the battery is being charged or when you think about the electron flow inside. However, the conventional electric current is seen as flowing *out* of the positive terminal.
Electrolytic Cells
In an electrolytic cell, which uses electricity to cause a chemical change, the cathode is the negative (-) side. Here, electrons also go *into* the cathode. This is where a process called "reduction" happens, meaning the cathode gains electrons.
How Electrons Move
A cathode is an electrode where electrons enter a device. Because electrons are negatively charged, the cathode itself is often considered negatively charged when it's letting electrons flow out of the device.
Related pages
Images for kids
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Glow from the directly heated cathode of a 1 kW power tetrode tube in a radio transmitter. The cathode filament is not directly visible.
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Cold cathode (lefthand electrode) in neon lamp.
See also
In Spanish: Cátodo para niños
