Why can a capacitor be charged by a battery (DC)?

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SUMMARY

A capacitor can be charged by a direct current (DC) battery due to the movement of charge within the capacitor plates. When connected to a DC source, positive charges accumulate on one plate while negative charges gather on the opposite plate, allowing the capacitor to store energy. Once fully charged, the capacitor acts as a DC-blocking element, preventing further current flow. This phenomenon is analogous to filling a bucket with water, where the bucket can hold water but does not allow it to flow continuously.

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  • Familiarity with capacitor operation and charge storage mechanisms.
  • Knowledge of direct current (DC) circuits and their behavior.
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Yoyo G
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Hello there,
I'm perplexed as to why the capacitor is DC-blocking, but the battery (DC) may charge the capacitor.
I'd never considered it until I recently read it in a book. I honestly have no idea what's going on.
If anyone has any idea why this happens, please let me know.
I've read some articles like the guide to capacitors, but I still don't know how it works.
Thanks!
 
Engineering news on Phys.org
In charging process of condenser
Plus charges are gathering to one plate. Minus chargers are gathering to another or in other words plus charges are leaving from another plate, so we see as if plus current go through beyond the plates. DC-blocking you say comes after a full charge.

Ref. https://www.feynmanlectures.caltech.edu/II_18.html Fig.18-2
 
Last edited:
Yoyo G said:
I'm perplexed as to why the capacitor is DC-blocking, but the battery (DC) may charge the capacitor.
A bucket can also block the flow of water, but you can still fill (and empty) it.
 
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