How do positive charges move in a circuit, when only electrons move.. ?

Question

This has bothered me for a long time. Electrons have negative charges, and they are the ones that move as electric current flows.. right? But apparently positive charges move as well to generate energy.. What is really going on?

Answer 1

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positive charges don't move unless it's an electric current through an ionic solution or something related to that.

Electron motion is what is physically going on in conduction. The field is applied and the reference direction of the current is in the "direction that positive charges move." In bulk, positive charges moving to the left is equivalent to equivalent negative charges moving to the right at the same speed.

When you get to semiconductor physics, electron motion becomes more complicated and in some cases is actually easier to describe as motion of a "hole," or an energy state that is not occupied by electrons. Think of it as a whole crapload of electrons cascading around such that it looks just like some tiny little positive charge is moving forward.

Electrochemical reactions shove electrons out the negative terminal of the battery, equivalently "shooting positive charges out of the positive terminal," even though it's really accepting electrons from the positive terminal.
Generators work by moving a coil of wires around relative to a magnet and by a much more complicated force shove electrons around.

Source(s):

near a B.S. in electrical engineering,
applying for Ph.D studies after graduating

Asker's Rating:

Asker's Comment:

Thanks a lot!

Answer 2

For conveniences in calculation every thing is tried to be kept positive and thus the quantity of electricity.As a convention charge of an electrion is NEGATIVE and proton as positive.Hence to keep the amount of electricity or electrical charge[coulomb or ampere] as positive the electricity is taken as the flow of positive charge[ or negative ie, opposite movement of negatively charged electrions.]
If charge of ELECTRIONS were taken as POSITIVE as A CONVENTION in all calculations of physics then electricity must be considered as flowing in the DIRECTION of ELECTRONS.

Source(s):

MY own logic.

Answer 3

hi,
firstly you need to understand that there are two types of current flows.

firstly there's electron flows - from negative to positive and

secondly there's convectional flow - from positive to negative

here's how they're used

conventional current flow

One should always analyse circuits on the convectional current flow. This is because all the Laws (KVL, KCL and other higher laws BJT Models) are analysed ( And given appropriate signs) after considering that the current flows in the convectional direction.

However when you study particular element in circuit ( say capacitor or a transistor, MOSFET, JFET) and when you need to know the electronic flow to understand some causes and conditions, you should consider the electronic flow.

**Electronic flow and convectional flow are always in opp. dir.

another thing to note is The conventional current is not a physical thing, its just used for analyzing circuits. But on the other hand the current produced by electron flow is a physical(meaning it exists) thing, whose direction is opposite to that of conventional current.

i hope this clears it up a bit for you

Source(s):

i did high school electronics and i'm an A+ certified tech

Answer 4

Do realize that in the recent past, people had a good working idea of electric circuits, but they never once used the word electron to explain them. They didn't know which type of particle was carrying the energy.

99 times out of 100, you can think exactly as people did in the eighteenth century, and never even once use the word electron...and still understand how your circuit works.

Positive charges CAN move, but usually aren't the energy carriers in most circuits that we build in metal wires. ELECTRONS are the energy carriers in most manufactured circuits.

The misconception occurs due to the fact that we define the "current" as it was understood before people were familiar with electrons. Let's give a full and better definition of current:

Current: the HYPOTHETICAL flow rate of positive charges that will produce the same field effects as whichever actual charges are doing the flowing.

Many people blame Benjamin Franklin for his ignorant mistake when defining sign convention, and imagine that the following is the first action that would be taken once a time machine is invented:
http://xkcd.com/567/

But, we must also realize that the electron doesn't have to be the charge carrier. IT only is in most circuits made by man's technology. BUT, if you examine what nature made when making animal neurocircuits, it ISN'T free electrons that carry the energy...it is POSITIVE ions of usually sodium (sodium ions are 11 positive protons, 10 electrons and 12 neutrons...so they are net positive particles). So sometimes there is a positive charge carrier, and other times, there is a negative charge carrier. There usually isn't a dual charge carrying though.

In metal wires, we don't see the positive nuclei of the metal atoms move, because they are constrained in a crystal structure, AND they have thousands of times more inertia than the electrons. They aren't significant in carrying the electrical energy. Of course, the entire wire can as a bulk object move, but that isn't the point.

Only a select few of the electrons are doing the flowing. But remember, we still say that current is in the direction that hypothetical positive charges would need to flow to make the same field effects, so the conventional direction of current is opposite the actual flow of electrons.