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In a DC circuit with a battery and a capacitor how do electrons on the capacitor plate connected to positive terminal flow? It seems the voltage between them and the positive terminal of the battery is equal to 0 volts.

If the answer is that the electrons will flow to the positive terminal of the battery despite there being no potential difference because we are talking about ideal wires of no resistance then how will they flow through real wires that have resistance to the positive terminal of the battery? What gives them voltage? Are they somehow pre-charged with electric potential energy from the capacitor itself? If so, how?

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2 Answers 2

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The negative plate of the capacitor is connected to the negative terminal of the battery and, the battery negative is a fairly unlimited source of electrons.

So, electrons "gather" at the negative plate of the capacitor because they are attracted by the positive voltage on the positive capacitor plate.

The gathering of electrons on the negative plate repels electrons from the positive capacitor plate until equilibrium is reach and there is no more electron flow.

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  • \$\begingroup\$ So what I’ve understood from you is that the repelling force is what gives the electrons electric potential energy to face the resistance of the wire until they reach the positive terminal of the battery, right? \$\endgroup\$
    – Ragtaglm
    Commented Sep 16, 2023 at 9:39
  • \$\begingroup\$ No, that's not true. BTW, this is an electronics site and, if you wish to get a more precise answer ask on physics.SE. Regarding your comment, if it were true then the positive plate would keep supplying electrons to the battery and, of course this doesn't happen with a capacitor. \$\endgroup\$
    – Andy aka
    Commented Sep 17, 2023 at 11:30
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You forgot the electric field inside the capacitor.

The voltage source puts more electrons on the negative plate of the capactor and sucks some from the positive plate. This process stops once the field strength is equal to the voltage applied.

Remember that voltage is a potential difference.

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