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[Phys-L] Fw: non-polarized capacitor

From: John Denker <>
Sent: Wednesday, February 24, 2021 2:38 PM
To: Jeffrey Schnick
Subject: Re: [Phys-L] non-polarized capacitor

On 2/24/21 12:00 PM, you wrote:

Sorry. Had I realized it wasn't a typo, I would have asked on
phys‑l. By the way, I find this idea of using two electrolytic
capacitors to make a non-polarized capacitor very cool. It is new to

Feel free to move the discussion to the list if you like;
nothing I have said is private.

I disagree with item 1

Definitions snipped ... but I appreciate the clarity.

If the two capacitors were ideal,

Discussion of ideal capacitors snipped. We agree on this.

In the case of the electrolytic capacitors,
charge is leaking out of the
central conductor. This makes the central conductor acquire a
negative net charge.

I disagree with your model of leakage.
The current doesn't come out of nowhere; it flows across the
capacitor gap. So when it is charging one plate of the capacitor,
it is discharging the other, so the net effect is pure gorge, not
an unbalanced charge, not a free charge. The leakage does *not*
violate Kirchhoff's so-called laws.

Just now I added some discussion and a diagram that may help.
It shows ideal capacitors plus an explicit model for the leakage.
This may make it easier to see that the leakage sub-circuit is
just gorging and disgorging capacitors in the usual way.