Imagine a simple circuit, say a light bulb and a battery. Electrons move from the negative terminal, through the bulb, and back to the battery. The net change in number of electrons at any one point is zero. The energy isn't in the electrons themselves, but in the motion of those electrons. Electrons in must equal erlctrons out.
Even a battery doesn't store electrons. It uses the energy carried by those electrons to reverse a chemical reaction. The energy is stored chemically.
If you think about it, the electrons belong to the physical materials in the circuit. You can't really add or remove electrons* as electron count is a fundamental property of those atoms. If you somehow removed electrons from the system, you'd be changing those atoms and the system would no longer be able to pass current at all.
*you can, of course ionize atoms by adding or removing electrons, but that's not exactly what happens in electric circuits
Electrons are not electricity, they just carry it. Kind of. It's really complicated.
In order to get a sustained current, you need to put electrons in one end and take them out from the other in equal numbers. Thus mass doesn't change.
However, if you're talking about static electricty, you can actually create a mass imbalance by taking a few electrons away from one side or putting some electrons on the other. It's a very, very, very small change in mass.
Whoa, really? Their answer was pretty spot on to your question. Why take such a hostile attitude when it’s your own inability to understand? I’m shocked to see such an ignorant and condescending comment being upvoted.
There’s nothing wrong with not understanding a technical explanation and asking for it to be simplified to your level of understanding, but this is not a simple concept to explain because it is ACTUALLY complex and counterintuitive. How is it their fault?
I'm just trying to answer your question, but I don't think you're exactly clear on what you want to know. It's ok, no need to get defensive about it.
Whether or not 'one end of the wire gets heavier' depends on what your doing. If you are using the wire to power an LED from a battery, then no, because electrons are removed from one end and placed into the other at equal rates. Charge and mass within the wire are both globally and locally conserved.
If you do something where charge/mass isn't conserved such as removing electrons from one side (i.e. by rubbing a fork on a carpet) or by using an electric field to 'tilt' the electrons to one side, you can create a (very small) mass imbalance. This activities are not usually considered to be useful electrical current.
You're talking about conventional current, and it's nothing more than a polite fiction. We model circuits as current moving from positive to negative, but with the implicit understanding that the real charge moves the opposite direction.
Positive charge carriers do not actually exist[0]. There's only electrons and holes they can go into. We can talk about the movement of holes, but that's a virtual charge carrier at best.
Conventional current is just a convention. It's what we started with (because Franklin was wrong) and it's too much effort to change now. In practice, the distinction almost never matters. Sometimes it does, but not enough that it's worth overhauling the entire field of electronics.
[0] of course positrons and protons exist, but they aren't relevant to electronic circuits
Yes, but to an unmeasurably small degree. Electromagnetism is very strong, so you never see the density of electrons change by very much, or the situation will correct itself quite violently.
A difference in voltage between two points in a circuit is a difference in concentration of electrons at those two points, and since electrons have mass that's not quite zero, the location with the higher concentration of electrons will have very slightly higher mass density. But this is true for any electric potential (voltage) difference, whether or not there's any current flowing.
An electron has .05% the mass of a proton, and only a small imbalance of electrons and protons is necessary to generate extremely strong electric fields by earthly standards.
Imagine a loop of pipe filled with water, and a pump pushing the water: The water moves around the pipe. The movement doesn't cause any part of the pipe to get heavier.
Imagine a different scenario, where the pipe ends in a big box: This time the box does fill up with water, and gets heavier.
Mapping the analogy from water back to electrons: a loop of pipe is like a loop of wire and a battery; while the pipe ending with a box becomes a capacitor or antenna, and that will leak[0] before you can measure the mass change — but technically yes the the mass of any given wall of a capacitor or of an antenna will be very slightly changed by this sort of thing.
For a sense of scale, to get a total charge of 1 coulomb using electrons, the mass of those electrons will be about 5.7 nanograms, and trying to squeeze that much charge into the last millimetre of some length of a wire 1mm in cross section diameter, involves about 60% of the energy in this explosion: https://www.youtube.com/watch?v=wqKn_3iJOP4
As nothing gets close to being able to hold that kind of energy, even if you're trying to accumulate a lot of excess electrons, those electrons leak well before even coming close to nanograms of excess mass.
Bruh its simple physics, does one end or the other get lighter, by all measures we care about, not really, the mass of a proton or electron is beyond any consumer hardware measurement. I doubt it would matter beyond extreme scenarios or controlled experiment
The answer is yes but you can't practically observe it. The electrons repel each other so strongly that you can't accumulate enough of them in one place to be able to observe change of mass of that object.
You can move whole charged atoms, that's a form of electricity too, and it can add observable amount of mass, like with electroplating or welding. But these very quickly turn electrically neutral after depositing.
Because of the mass of the electrons moved from one thing to the other.