Since current caused by the movement of electrons in the wire so shouldn’t current be define rate of flow of electron?
In: Physics
I am going way back in my memory, as I no longer work in electronics, and college was a long time ago.
As I recall, a single electron moving between atoms is actually quite slow. An electron entering a wire from a battery and travelling to the other end of a wire can be measured in seconds or minutes. However, as it moves along, it pushes the electrons in front of it, and it is the charges that we detect moving at nearly light speed. Kinda like a hose. The water entering one end of a hose can take some time to finally come out the other end, but as soon as you turn the water on, it starts coming out the end of the hose almost immediately, because it is being pushed along by the water entering at the other end.
I stand to be corrected by anyone with knowledge obtained from this century.
The discovery and application of electricity predates the discovery of the electron by many decades.
By the time electrons were found and their charge measured, the nomenclature of circuitry had already established current going from positive to negative.
It is arbitrary.
Because for current it doesn’t matter what charges are flowing. You can generalise equations to be applicable for any charge even though in practice its usually electrons that are flowing. For electrodynamics this is unnecessary specific we talk about charges and their motion in general.
For electronics the type of charge is also unimportant but the specific amounts become more important.
For understanding how conductors work and how we can make them more conductive we are talking matterial science where the properties of the main charge carriers like the electrons become more important.
So the principles that govern what charges do are independent from what charges exist but once you are looking at actual matterials whats there become the main question. Like how in quantum mechanics you can have spin 7/2 fundamental particles, the fact that (as far as we know) they don’t exist is another thing.
It’s very common to talk about currents in contexts in which the charge carriers are not electrons. For example, in chemistry, you often talk about a current of ions moving through a solution. From the perspective of (classical) electromagnetism, any two point particles with the same charge/mass ratio have exactly the same behaviour, so it’s common to talk about arbitrary charges, in the same way that a mechanics textbook will talk about general terms like “masses”, “objects”, or “bodies” instead of specifying that everything is, say, a brick.
If you mean that we should measure currents in electron-charges per second instead of amps, that would just be unwieldy for most purposes.
Because if you had a flow of electrons in one direction and a flow of protons in the other direction, the net flow would be neutral, but your system would measure a current flowing in the first direction.
Ben Franklin had a 50/50 chance of getting it right and [he guessed wrong](https://xkcd.com/567/).
There are a few videos by veritasium on Youtube that explain these things if you are interested, but electricity isn’t *fully* created by the movement of electrons alone, but rather by them pushing on each other.
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