Comment by calamari4065 | Hacker News Reader

Comment by calamari4065 | Hacker News Reader

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No.

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.

So electrons aren't actually moving from one place to another?

Ben Franklin’s definition of current, otherwise known as the standard one, has positive charge carriers.

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

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.

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