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
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.
At least in german education you are usually taught about the concepts of technical and physical current flow.
Technical current flow is form positive to negative where as the real phyiscal current flow is the movement of electrons from negative to positive.
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.
Because Benjamin franklin just guessed which way it went and nobody was bothered to change it when they found out he was wrong.
* Back when Benjamin Franklin studied electricity, he discovered that current flowed but wasn’t sure which way was positive and which way was negative….
* So he guessed.
* Later they found out he had it backwards.
* But they had used his conventions for so long that they kept it.
* So “current” and flowing electrons are the same thing just the signs make it seem otherwise.
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.
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