Eli5 : After seing the meme of a guy going back in time and unable to answer to the question “how is this so-called electricity made?”, I’m actually really asking myself the question.



Eli5 : After seing the meme of a guy going back in time and unable to answer to the question “how is this so-called electricity made?”, I’m actually really asking myself the question.

In: Engineering

There are a bunch of ways. Silicon-based semiconductors will be quite beyond a medieval peasant so getting it from light is out. Mechanical is dead simple tho, get a magnet, get a metal wire, move one across the other fast, BAM you induced voltage. If you cover the wire in insulator (paper, wax infused thin cloth, etc. work fine) and make a tightly wound coil, the effectiveness of the generator skyrockets. Do whatever for energy source, steam machine, water wheel, windmill, a serf running really fast in circles holding a crank. You can also make a chemical battery, only needs two different metals and something acidic to dip them into.

The most common way is mechanically. A generator spins coils of wire inside of magnets which generates an electrical current. We use generators in nuclear power plants, coal power plants, wind turbines, etc. Wherever you have something spinning there’s a generator attached that generates power. Another way is photovoltaically. Solar panels are made of a special material that generates power by exciting electrons which jump between energy states which generates electricity. Electricity can also be made chemically. A substance that wants to get rid of electrons is paired with a substance that wants electrons. This is commonly known as a battery. When the two substances are connected via say a wire, the electrons flow which produces electricity. The short answer is there are a number of ways to do it and it can become very complicated trying to explain it all but I think those are the basics.

Take a big coil of wire – a metal, full of electrons. Electricity is just the movement of electrons.

Because electrons are electrically charged, they create and respond to electric fields – think of when you rub a balloon against your hair, statically charging it. The hairs push away from each other. That’s the negative charges creating negative fields. Negative charges don’t want to be in other electrons’ negative fields, so they start pushing away from each other.

A magnetic field is the same thing as an electric field, really – that’s why we call it “electromagnetism”. The only difference is how you look at it.

Put some magnets in the centre of the big coil of wire. The magnetic field from those magnets will start to push on the electrons in the wire.

If you start turning those magnets, the field will turn too – and as it moves, it’ll push the electrons with it. Because it’s a coil, or a spiral, as you spin around the middle, you also move to one of the ends.

The electrons moving out of the end of the coil is electricity.


Literally a hundred comments later asking the same few questions:

1.0) You can’t deplete a wire of its electrons. Electricity works in circuits, closed loops of wire – as you push the electrons out of the wire, the pushing force affects the whole circuit and more electrons are pushed back into the other side of the coil, and they then get pushed around again by the magnets.

2.0) The electrons start in the wire. Everything is made of atoms and atoms have electrons. In metals, those electrons are free to move around, but they’re more bound up in non-metals.

3.0) You can find naturally occurring magnets in the form of minerals like magnetite, or lodestones, but you can also make them by rubbing two pieces of iron together in the same direction a few thousand times.

3.1) “In the same direction” means the strokes are always the same, you don’t go back and forth. Think of it like combing your hair: you always brush in the same direction.

4.0) I know this is an oversimplification, that’s the point. It’s an ELI5. Stop telling me “Well actually it’s a lot more complicated-“. I know you can carry charge through other means, not just electrons; I know positive charges are conveyed as holes in the electron sea; I know. Whatever your correction is, I know, and I deliberately left it out to make it simple enough for a 5 year old. As is the sub’s reason to exist. If your 5 year old can crunch the numbers on Lenz’ Law, good for you, go breed an army of your fucking superkids and stop bothering me.

5.0) Really late in the game here, but: “In OP’s comment he says-” – no he doesn’t, _she_ does.

Seeing the ansewers, where would I find a magnet in the medieval times? How can I make one?

Gonna attempt this.

Electricity is what we call it when electrons, a tiny part of atoms, that make up everything, move through a thing (usually metal or “electrically conductive” material)

We can make that happen many ways, like rubbing two things together (static electricity from rubbing a balloon on your head), a magnet moved by a coil of copper wire (electro-magnetism).

When we make these electrons move, we call certain parts of that movement certain names to make things easier, voltage is how many electrons want to move through a wire, amperage is how many is moving at once, and ohms are how hard it is to move them through a thing.

Late but whatevs. I WANT to offer an answer so I’m gonna..

Electrons in wire are like water pressure in a pipe. So first, let’s look at how water moves, flows, and behaves.

Water is not compressible. You put it in a balloon and deform the balloon, and it will have the same volume as before, just in a different shape. Air? Not so much. Try putting a balloon full of air in the fridge if you don’t believe me.

This is important to the analogy, because electrons in a wire can’t be compressed either.

So if I were to take a long pipe, fill it full of water, and shove hard on the water, the water in the pipe would push on the other water, until it came out the other end with the same force I shoved with.

Now, electrons have regions around the atoms that they will be hanging around, as a function of their Energy Level. Some atoms, like those of conductor materials, have electrons that are rather easy to shove into their neighboring atoms. But any atom can only sponsor so many electrons at once in any particular region, and some regions are very hard to get shoved to, requiring great force, just like a section of pipe can only hold so much water, and if you put too much in you may swell or even burst the pipe.

So, now that you are thinking of pipes, *the wire acts as a pipe for the electrons*.

Finally, electrons are influenced by magnetic fields. If you see a magnetic field, that is the product of a moving electron… Though sometimes the field is created by spinning more than moving per se. If you generate a magnetic field around a wire, you are shoving the electrons in it because when a magnetic field changes, electrons are changing.

So by moving a magnet across a wire, you push on the electrons. If the wire doesn’t have a “closed circuit”, you will have a hard time of it because there is nowhere for you to push those electrons and they will swirl around like water in the pipe, just making it hot. If the wire creates a closed loop, you just shove the electrons around the loop. Shoving electrons around, by changing magnetic fields around them, specifically to create this turbulent motion of electrons, is how induction heating works.

In addition to being able to actively “pump” electrons through the wire “pipe” using a magnetic field, you can also do something akin to putting a water tank on your roof and letting gravity draw the water through the pipe. This is how batteries work, though the force that draws the electrons “down” through the “pipe” is still electromagnetic: one chemical has electrons and is separated from another chemical that wants them. They want to exchange electrons (this is how most chemical reactions work!), And by connecting the ends of a wire to each pool of chemical, you allow the electrons to flow between them, from where there are “too many” to a place where there is “too much”.

Finally, how do we get work done with this arrangement? Well, you know how I said shoving around electrons causes the magnetic fields to change? Magnets can pull on other magnets, and you can make a magnet exist (or not!) By whether you are moving electrons around. Want to create a magnet temporarily to pull on a bit of iron? Shove some electrons through a loop of wire, and you can pull on stuff! Install another coil, and you can pull it back the other direction (or to the center) depending on which coil you shove them through, such as “both”.

Want light? Shove the electrons through a tiny space, and they will be forced to “crowd around” and get shoved up to higher energy states than normal, and then when things calm down a little for them, they will pop back down, and the distance they move (moving electron) creates a moving *wave* in the electric and magnetic fields, and that’s what light is!

For the lazy:
Spinning electrons are magnetic. All electrons “spin”. Therefore all electrons are magnetic, and can be shoved with magnets. Metal wires have fixed electron counts, but you can shove them around inside the wire, because magnets can shove other magnets, and as a result, you can express that magnetic force that you shove into the wire elsewhere along the wire to do work.

Here’s a major oversimplification of it

I’ve split the explanation into 4 parts:

– Atoms
– Electricity
– How the light bulb works

First off, atoms and what they’re made of:

Everything in the world is made of atoms, but what are atoms made of? Well we have 3 parts of an atom, neutrons (a particle without a charge), protons (a particle with a positive charge) and electrons (a particle with a negative charge). We call these subatomic particles, because they’re a step below atomic particles like atoms. (There’s a step below subatomic particles, but that’s a whole other can of worms).

Now protons and neutrons really like each other so they’re stuck together in the center of the atom while electrons are only loosely attracted to the other 2, so they orbit around the center like our satelites do around earth or the planets around the sun. Different elements are made of different amount of electrons, protons and neutrons. It takes a lot of energy for protons to be separated from the neutrons in the center, but a loooot less energy to move around the electrons, cos you know they only kinda like being near the center of the atom and not mooshed together like the proton.

Here’s where we actually get to electricity:

All energy in the world is transformed, not created. Everyday we see things like a light bulb taking electrical energy and turning into heat and light, or a car turning combustion (heat, light, expanding gas kinetic energy, sound vibrational energy even) into mechanical kinetic energy that makes it go vroom.

Now electricity is a big branching word we use to cover energy that’s created using the movement of electrons jumping from atom to atom. There are many ways for electrons to be influenced into moving, but we won’t go into that detail cos it’s quite literally a 1/4 year high school topic.

One of the most popular is to create a positively charged deficit so the negatively charged electrons will start moving towards it, cos we’re gonna tack on the fact that everything in the world also likes to be balanced and in equalibrium. We see this in batteries, that’s why we have a positive end and a negative end,the battery has chemicals and things in it that have a tonne of electrons on the negative side, but a lot less on the positive. When you attach the battery to a circuit,the electrons see a path for them to run through to the positive side so they scurry through the circuit to try to balance out the battery and become equally charged on both sides.

Another way to move it is glorious magnets. At some point in time in the past after many years of research and discoveries, we found out that magnets effect electrons. Now I’m not gonna dive into it,cos electromagnetism is a whole topic with a super interesting history involving people who’s names are still used in words today like, voltage, amps, Faraday cages, galvan etc. All you need to know of magnets effect electrons so we made things to push them around like electric motors and such, google may give you a much better explanation than I ever could haha.

Now finally an example of electricity at work:

The light bulb, I’ve already explained how electrons want to move through circuits because of something like a battery, but why does the traditional light bulb do what it does? The traditional light bulb is just a thin cable, enclosed in a glass bulb, filled with non flammable gas. That’s it, why it took Edison so many attempts to come up with it is baffling, but anyway. When you have a electrons running through it,several things start to happen.

The first is the thin cable,being so thin the electrons coming in through the thick cable outside of the bulb have to squeeze through, but because of another scientific principal, it has to go faster in a tight space to make sure the same number of electrons come out the other side. This means they’ve a lot faster in the cable. When this happens, it causes a lot of friction. (Did he say friction?!?!?) YES, friction can be created from electrons,but at the speed they’re moving at it very quickly transforms the it into heat energy and light energy.

That’s how it works, something to note is that non flammable gas we mentioned earlier is there to make sure the thin cable doesn’t start a fire from the heat and melt itself. Combustion requires oxygen,so the bulb is filled with a gas that is not oxygen or otherwise flammable, in case someone breaks the bulb.

TLDR: Electricity is what we call the generation and usage of energy when we manipulate subatomic particals called electrons.