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I'm currently working through an AP revision guide. The section on charging a capacitor outlines the following steps:

  1. When a capacitor is connected to a battery, a current flows in the circuit until the capacitor is fully charged, then stops.

  2. The electrons flow onto the plate connected to the negative terminal of the battery, so a negative charge builds up.

  3. The build up of negative charge repels electrons from the positive terminal of the battery, making that plate positive. These electrons are attracted to the positive terminal of the battery.

  4. [The description continues]

My question here is: Shouldn't the last part of step 3 say "These electrons are attracted to the negative terminal of the battery"? as that is where the negative charge is building up. Slightly confused about this but I was hoping it's just a typo.

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  • $\begingroup$ The battery pulls electrons from the positive side and moves them to the negative side. In step 3, the electrons are attracted to the terminal and go into the battery. $\endgroup$ – LDC3 May 3 '15 at 17:32
  • $\begingroup$ Which physics book? $\endgroup$ – Qmechanic May 3 '15 at 17:48
  • $\begingroup$ @Qmechanic: An AP revision guide (I didn't think many people would be interested in it, hence the omission). $\endgroup$ – user45220 May 3 '15 at 17:49
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No. Step number two already mentions electrons from the battery flowing into the negative terminal of the capacitor, giving the negative terminal a negative charge. Step number three is talking about electrons flowing out of the positive terminal of the capacitor, giving the positive terminal a net positive charge.

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  • $\begingroup$ But then it says "these electrons are attracted to the POSITIVE terminal of the battery". If they're flowing "out of the positive terminal", why are they attracted to the positive terminal? This is what is confusing me. $\endgroup$ – user45220 May 3 '15 at 17:27
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    $\begingroup$ I see... step 3 should say: "... repels electrons from the positive terminal of the capacitor, making that plate positive..." Charge is repelled from the positive terminal of the capacitor into the positive terminal of the battery. $\endgroup$ – Gabe Noblesmith May 3 '15 at 17:34
  • $\begingroup$ I would really appreciate it if you could also answer my question here: physics.stackexchange.com/questions/180861/… (It's basically about step 2 above) $\endgroup$ – user45220 May 3 '15 at 17:52

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