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I have gone through the following links, but they all talk about moving charges in some sense: Charge capacitor with static electricity , How to charge a capacitor with static electricity? , Can a Capacitor Recharge From Ambient Static Electricity? .

Can we charge a capacitor merely with static electricity where charge is found accumulated on a space but doesn't move?

Can we charge a capacitor merely with strong electric field such as by placing the high voltage capacitor between the two terminals of secondary coil of a 1:4000 or 1:10000 step up transformer?

When we connect the terminals of such step up transformer we can see the arcs which means there's a super strong electric field between the two terminals. If we can place a capacitor in between, will it charge it fully? Will it charge slowly or quickly? Which parameter(s) will affect the charging speed?

NOTE: This question may appear a duplicate of this -- Can you charge a capacitor with very high voltage and no or little current from secondary side of a step up transformer?, but the answers are different. In this question the answerers have expressed their opinion about the possibility of charging a capacitor with just electric fields and no current, however in the question in the pasted link, answerers have not pointed out any such possibility. That may be because of the difference in the verbiage of the question, that caused the reader to think differently. If a synonym of a word makes the reader think differently, it should be considered a different message, so please consider this a different question.

Yogie
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    Perhaps all those links talk about moving charges, because you have to move charges to charge a capacitor. 'Static' electricity is a misnomer. You can charge a capacitor with 'static' charge, when the charge moves into the capacitor, it ceases to be static! 'Merely' is a bad word, just like 'just'. Things are almost never 'merely' simple. – Neil_UK Nov 09 '22 at 08:30
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    There is an error in your logic. Charges don't somehow mysteriously accumulate without moving to the place where they accumulated. – Justme Nov 09 '22 at 09:05
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    Your final paragraph sounds like you're doing something really dangerous. – Chu Nov 09 '22 at 11:02

2 Answers2

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I am going to say "No" to this one. Moving two "things" into contact, or close proximity, with different electric fields will always result in displaced electrons. In other words, at some point some amount of charge will flow.

Dirk Bruere
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When there's a charge there's an electric field. A capacitor holds charge, so the capacitor stores energy in a form of electric field between its conductive plates. And this electric field generates a voltage across them.

$$ V = \frac{q}{C} $$

To charge a capacitor the potential difference across the plates should be increased, so more charges can be added. In other words, a potential difference of greater than the capacitor's present value should be applied across the plates.

So the key point here is the electric field applied across the capacitor's plates.

So,

My question is whether we can charge a capacitor merely with static electricity where charge is found accumulated on a space but they don't move?

If the generated electric field is enough to beat the capacitor's present field across its plates then it'd be possible.

strong electric field such as by placing the high voltage capacitor between the two terminals of secondary coil of a 1:4000 or 1:10000 step up transformer?

If the field generated by the transformer secondary generates higher voltage across the plates of the capacitor then yes, charging the capacitor is possible. However, the voltage across the secondary, therefore the generated field, will be AC so the capacitor will be periodically recharged and discharged because during the half of the cycle charges will be pushed, and during the remaining half cycle the charges will be pulled (attracted).

Rohat Kılıç
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  • To prevent the discharging and recharging of capacitor we can connect the capacitor in series on both terminals and then connect the ends to load, should the load run? And if load runs this setup will not only step up voltage, but also the current, and eventually stepping up the energy, which is not possible as far as I am concerned. – Yogie Nov 09 '22 at 08:30
  • @Yogie you are using "parasitic capacitance" (i.e. capacitors that we didn't draw on the circuit diagram) to charge your capacitor. Imagine you have two big plates (which are the ends of the transformer) and you are putting two smaller plates in the middle, between them. You are counting only the middle two plates as a capacitor, but actually, you have at least 4 separate capacitors here and they make a voltage divider. – user253751 Nov 09 '22 at 18:46