Sherif A. Tawfik Abbas, Research Fellow, RMIT University/The Conversation
Everything is made from atoms
Everything is made from little tiny things called atoms. They are so small we cannot see them. They are much smaller than chickpeas, rice, ants, and ant eggs.Because atoms are so small, we need a lot of them to make things. For example, a grain of rice has billions and billions and billions of atoms. Those atoms make up the rice, in the way LEGO pieces make up a LEGO car or house. They atoms click together and hold onto each other. Even though an atom is extremely small, it is also made from even smaller things.
One of the things that make up the atom is called an “electron”. Electrons have many jobs. Some electrons help the atoms hold onto each other. Scientists call these electrons the “bonding electrons”. Bond means to stick together.
Other electrons just keep running around in the atoms. They are free electrons and they’re always on the move. Sometimes, they can move from one atom to another.
Electricity happens when electrons move from one atom to another.
Electricity in the power cable
So, the story so far: we know there are billions and billions and billions of atoms. A leaf, a plastic cup, your pet – they all have electrons. Some things, like metals, have more free electrons than other things. A plastic cup, for example, doesn’t have as many free electrons. They might be plugged into the TV or computer or a phone charger. Power cables have a huge number of free electrons.When the free electrons in a power cable move from one atom to another, almost all in the same direction, you get something called an “electric current” running through the power cable.