In school, you probably heard something like “electricity is the movement of electrons through a conductor like a wire.”
And yeah, that’s not totally wrong.
But to really understand electricity, we need to zoom in and think small. Like, atomic-level small.
Everything around us—whether it’s your coffee cup or your phone charger—is made up of atoms.
The Structure of The Atom
1. Protons
These little guys chill in the center of the atom, known as the nucleus.
They have a positive charge (+), and the number of protons an atom has decides what element it is.
For example, if an atom has 1 proton, it’s hydrogen. If it has 6 protons, it’s carbon.
Think of protons as the “ID card” of an atom—they define who it is..
2. Neutrons
Neutrons are like the proton’s neutral buddies, hanging out together in the nucleus.
They don’t have any charge—so they’re not positive or negative—but they’re crucial because they help hold the nucleus together.
Without neutrons, all those positively charged protons would repel each other (since positive charges push away from one another, like magnets).
In simple terms, Neutrons act like a buffer or “insulator” in the nucleus, keeping things stable.
3. Electrons
Lastly, we’ve got the electrons.
These are the tiny, negatively charged (-) particles that orbit around the nucleus, sort of like planets orbiting the sun.
Although electrons are much smaller than protons or neutrons, they’re super important because they’re the ones that move when electricity happens (hence the name “electricity”).
Electrons don’t just fly around randomly though. They move in specific orbits or energy levels around the nucleus, which we’ll get into later.
The Atom’s Electromagnetic Force
What keeps the atom together and makes it kinda stable is the electromagnetic force.
Basically, the nucleus is positively charged, so it acts like a magnet and pulls negatively charged electrons.
The more protons (positive charges) an atom has, the more powerful its magnetic force, and the more electrons it can pull.
Now, atoms like to be stable. And by stable here, I mean they want to become neutral by having the same number of electrons and protons.
For example, carbon (C) has 6 protons, so ideally, it only wants 6 electrons to become stable.
Once a carbon atom has its 6 electrons, it doesn’t want to lose or gain any more electrons.
Well, unless something forced it to.
Electrons Energy Levels
We mentioned earlier that the nucleus (+) pulls the electrons, preventing them from escaping the atom.
However, electrons don’t just crowd into the space closest to the nucleus.
Instead, the nucleus forces the electrons to move in specific paths or shells, called energy levels.
- The first shell (energy level) can hold only 2 electrons.
- The second energy level can hold 8 electrons.
- The third level can hold 18 electrons.
Electrons always fill the closest shell first. Once that closest shell is full, the next shell starts filling, and so on.
Now, here’s the important part: the further the electron is from the nucleus, the weaker the pull from the nucleus becomes.
This means electrons in outer shells (like the third or fourth) are less affected by the electromagnetic force compared to those in inner shells. As a result, they’re easier to remove.
Think of it like magnets and coins.
If the coin is close to the magnet, it sticks firmly and is hard to pull away. But the farther you move the coin from the magnet, the weaker the pull, and the easier it is to take the coin away.
This brings us to the concept of valence electrons. These are the electrons in the outermost shell and they’re the ones that can create electricity.
How Current Is Created?
So far, we’ve been talking about a single atom. Now, let’s think bigger—a material made up of many atoms connected together.
In a material, the valence electrons (the electrons in the outermost shell) are loosely connected to their atoms.
Because of this, they can easily escape from one atom and jump to another.
This movement of electrons from atom to atom is what we call electricity.
When a material has a lot of these free-moving electrons, it’s considered conductive (like metals). If it has very few, we call it an insulator (like rubber).
But wait—if conductive materials have free electrons moving around, why don’t you get electrocuted every time you touch a piece of metal?
Well, because it’s not electricity that shocks you, it’s current. Current is the organized flow of electrons in one direction.
In a normal piece of metal, the electrons move randomly in all directions. This random movement isn’t enough to create a strong current, so you’re not getting shocked just by touching it.
To create a current, we need an external force—like a battery or a power source—that pushes these free electrons to move in one direction. This force makes the electrons flow through a path or circuit, and that’s when we have a current.
