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Q & A: current flow

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Most recent answer: 11/20/2009
Q:
There are two conflicting statements on current flow in an electrical circuit on this site, and a third on other sites. As an electrician (masquerading as a trainer), any of them will suffice, as long as it is consistently used. When a light bulb does not work, I do not ask which direction the current was flowing when it failed, or which electron failed to flow correctly. I replace the light bulb. 1) Current is the energy wave that propagates (opposite the electron's direction of travel)when an electron is pulled from it's atom's orbit. Thus, current is actually "hole flow". The wave can be "harnessed" to do work, or convert energy into another form. 2) (on this site)Current is electrons moving from positive to negative (using the common references, understanding that this is not accurate). They are pushed by the positive potential of the voltage. in this explanation, the motive force (voltage potential) is positive (assuming a DC circuit for simplicity), and it is PUSHING the electrons. How does a positive potential repel a negative potential? How do we turn an electron particle into work using this model? 3) Current is electrons moving to a higher potential (from negative to positive). This seems more in keeping with traditional understandings that opposite charges attract, like charges repel. But how do we turn those electrons into work (energy) using this model? Any clarification will help. Thank you for sharing your expertise!
- Mark Shawley (age 41)
Seattle, Wa
A:
Your number (3) looks like the standard answer.

I can't follow the meaning of your number (1).

Could you send us the answer number or name where we said   (2)? We could then see if we need to fix it.

Mike W.

(published on 11/20/2009)

Follow-up on this answer.