Movement on a Pair of Wires It takes two wires, however, to make an electrical circuit: one wire carries the current one way away from the power supply to the load, and one wire carries the current the other way from the load to the power supply. One way of thinking about it is that the electrons, that leave the power supply on one wire, have to be returned to the power supply on the other wire, or the power supply runs out of electrons.
One way of thinking about it is that the positive charges, that leave the power supply on one wire, have to be returned to the power supply on the other wire, or the power supply becomes unbalanced. Both ways of thinking about electrical movement work; only one way or the other can be used at time.
Trying to use both ways at a time becomes confusing when trying to explain how electricity works to someone else. Power Movement Power , which is the transfer of energy, moves along a pair of wires for a complete circuit at nearly the speed of light. The problem with power movement is that it can't be explained as just electron movement or positive charge movement. Power movement is the combination of both electron movement negative charge movement and positive charge movement.
If you want to understand power movement, then you have to understand both negative charge the electron and positive charge movement. Electricity - No Agreement In order for me to say electricity flows one direction or the other, everyone world-wide has to agree on the definition of electricity. It's been over a hundred years since the electron was discovered, and still, there is no real agreement on what should be thought of as electricity.
For me, I choose to refer to electrons flowing in the circuit. The physical electrons as they move around a circuit seem more real than the perceived positive charge movement. Rather than saying "electricity is flowing", I try to say "electrons are flowing".
Specifying "electrons", to me, seems to work better than the ambiguous word "electricity". If you can get all the engineers and technicians, and all the educators and textbooks to agree on what is electricity, then I can tell you which way it flows. This was the convention chosen during the discovery of electricity. They were wrong! Electron Flow is what actually happens and electrons flow out of the negative terminal, through the circuit and into the positive terminal of the source.
Both Conventional Current and Electron Flow are used. Why does a current flow from positive to negative? Aritra G. Jul 23, Explanation: As on today, we know that electrons are negatively charged and thus, the conventional current flows in the direction opposite to the direction of electron motion.
Related questions When work is done on a positive test charge by an external force to move it from one location to Donate Login Sign up Search for courses, skills, and videos. Science Electrical engineering Introduction to electrical engineering Getting started. Current direction. Conventional current direction. Preparing to study electrical engineering on Khan Academy. Basic electrical quantities: current, voltage, power. Numbers in electrical engineering. Defining the standard electrical units.
Current timeTotal duration Google Classroom Facebook Twitter. Video transcript - [Voiceover] In the last video, we talked about the meaning of current, and current is defined to be the movement of charge, amount of charge per second.
We looked at a copper wire where electrons are carrying the current, and we looked also at a salt solution where both positive and negative ions are carrying the current across this imaginary boundary where we keep track of how many charges are moving.
So now, next we need to talk about how do we define a positive current? What does a positive current mean? So, I'm gonna move this up a little bit. And we're gonna get to something that causes some confusion.
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