I know that flow of electrons is not current, it is opposite to the direction of flow of electrons, is it just a convention? why such a convention was chosen if it is one. . Please correct me if you think i have very wrong assumptions.
In: Engineering
To add something I don’t see anyone mention, which might also make things more confusing. There’s something called the [speed of electricity](https://en.wikipedia.org/wiki/Speed_of_electricity), and like one would predict, it’s very fast, a fraction of the speed of light. What most people don’t realize is the “drift velocity” of electrons themselves is very slow. Which begs your question, what’s “flowing”? Electricity is electromagnetic *energy* that is propagated through electrons. Think of a [Newton’s cradle](https://en.wikipedia.org/wiki/Newton’s_cradle) with a hundred balls, and imagine perfect conservation of energy. Imagine the ball on one side coming down and hitting the adjacent ball. That momentum is going to travel down that line of balls. How fast? Some fraction of the speed of light. Then the ball at the other end pops up almost instantaneously. Same thing with electricity. Conductors in a circuit or power line are full of electrons that act as a medium for energy to propagate through. It’s the energy itself flowing, not so much the electrons.
The light bulb does not emit photons, it absorbs darkons. Everything around us is a “black body” and it constantly emits darkons. Light bulbs, much like the sun absorb these darkons so we can see.
Seeing some confusing answers here. I’m hoping I can tidy them up.
The short answer is that we observed a moving charge before we could observe a moving particle. WAY before. We had just loads of experiments and observations and formulae and then we saw it! We saw the moving electrons… and … they’re moving… the OTHER way. Oh, boy.
Now science has a choice. We can either pretend it never happened and change what we write down the opposite thing from now on and put an asterisk on everything we’ve ever seen.
Or.
We can (and typically do in science) respect the past as totally legitimate observation and separate the charge from the particle that causes it.
I could describe the movement but I think it is better to point to another thing this happened with, magnets. The Earth’s North pole (like where Santa lives) is a magnetic south pole and Antarctica is magnetic North. We called the north pole of a magnet the north pole because it points north. But like poles repel. Again, we’ve got a lot invested already, so we just note that one thing rather than changing all of everybody’s notes.
One idea to think about is to consider a typical x-y plane. By convention we think of upwards as “more positive y” and downwards are “more negative y”. However you could draw the x-y plane with the opposite convention for the x and y axis or both and it still works. So now upwards can be “more negative y”. It doesn’t change your idea of “up” or “down”, you just reversed the signs.
So increasing the flow of electrons one way simply makes the current flow “more negative” in that direction – which simply means it is “more positive” in the other. It is simply a sign convention.
We guessed that current flows positive to negative before learning about electrons. But all the calculations, theories, and core concepts still remain valid. To this day we use this as conventional current, and the actual movement of electrons from negative to positive as electron flow
It’s a flow of “holes”. Imagine a traffic jam where you all shuffle forward a bit when there’s a space, that space seems to ripple backwards as the cars come to fill the gap. Same with holes – electrons come to fill a hole, so the hole appears to flow in the other direction.
Current is flowing electrons, full stop.
The sign of the charge on the electron is negative, for historical reasons. This causes some odd things, but the change isn’t worth the effort. 5 electrons is -5 and 10 electrons is -10, that’s just the way it works. The sign was an unfortunate convention, but we’ve gotten used to it over the centuries.
voltage is the size of the hose, current is the pressure behind it. its like having a garden hose at 20psi vs one at 220 psi. more pressure means a thicker hose, hence larger gauge wire. Think of your car battery. It’s only 12 volts but can drop 1000 amps cold power in winter. That’s why the wires are so thick. Simplest explanation, in ELI5 terms. Also, positive is the spout and the water wants to come out the negative end (the end of the hose) to return to wonderful ground.
Flow of electrons is current. An ampere is one “coulomb” of electrons flowing past a point per second.
The one you’re thinking about is called “hole flow” where if you imagined the gaps between electrons( holes) as current flows, the gaps move backwards.
It is a convention that was chosen at random, because it was known that there were two “kinds” of electricity that canceled each other out. This was before electrons were known about. However, that doesn’t make it “wrong.”
*Usually* what is physically happening when we talk about current is flowing electrons, however that is not necessarily true. Current is the net flow of charge, not the flow of electrons. **Current is (flow of positive charges) – (flow of negative charges)**. In a normal copper electrical wire, it’s only electrons that are moving, and they are negative. But in a battery, both positive and negative ions are moving, in opposite directions. In a semiconductor, positive “holes” and negative electrons both move. In the solar wind, electrons and protons both move. etc.
Latest Answers