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Q & A: How can a battery circuit work?

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Most recent answer: 06/07/2015
Q:
Electric current depends negatively charged electrons.thenhow a electron can move from positive to negative in a battery?Because negative charged particles cannot attract to negative.
- Midhun Ajith (age 15)
kollam,kerala,india
A:

That's a deep question. If there were simply different electrical potentials at different places in a circuit, and electrons could move throughout the cicuit, they would quickly move to make the electrical potential equal everywhere and then current would cease. That tells you that there must be something else going on in a circuit with a battery. We've discussed the ideas a bit in previous answers:

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The key point is that it's not just the free electrons that are moving to minimize their free energy. Their motions are linked to the motions of other electrons in ions, and these are also moving to minimize their free energies. The ions have complicated free energies that depend on their chemical neighbors, not just the electrical potential in each region. In order to minimize these chemical free energies, some electrons have to move around to keep charge from buildeing up.

Please follow up if those answers are not enough.

Mike W.


(published on 06/07/2015)

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