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.
* 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.
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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