Question about high electric charge.

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Discussion Overview

The discussion revolves around the behavior of highly charged sheets in an electric field, specifically focusing on the effects of changing distances between the sheets and the implications for a transformer supplying power to maintain the charge. The scope includes theoretical considerations of electric forces, current flow, and the interaction of charged objects.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions how changing the distance between two charged sheets affects the current flowing through the transformer's primary winding.
  • Another participant suggests that the power supply unit (PSU) maintains the potential difference (PD) between the sheets and questions the necessity of current flow through the transformer for this maintenance.
  • A follow-up question is posed regarding the effect of introducing a positively charged ground sheet between two negatively charged sheets, speculating on the resultant forces.
  • One participant asserts that discharging one of the sheets to ground would create a short-circuit, potentially overloading the PSU.
  • There is a discussion about the need for effort to maintain the position of similarly charged plates and the relationship between charge movement and current flow.
  • Another participant describes the scenario of having two parallel-plate capacitors and how the introduction of a positively charged sheet would alter the net force experienced by the negatively charged sheets.

Areas of Agreement / Disagreement

Participants express differing views on the role of the PSU and the implications of changing distances between the sheets. There is no consensus on the effects of introducing a positively charged sheet or the specifics of current flow in relation to the transformer.

Contextual Notes

There are assumptions regarding the behavior of electric fields and forces that are not fully explored, such as the exact nature of the interaction between the sheets and the ground. The discussion also does not resolve the mathematical implications of the changing distances or the specifics of the transformer operation under these conditions.

Who May Find This Useful

This discussion may be of interest to those studying electrostatics, electrical engineering, or anyone exploring the dynamics of charged objects in electric fields.

Low-Q
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Hi,

If I have two sheets which is highly electric charged, and with the same polarity of 100kV with respect to ground.
The sheets are 10cm^2, aligned in parallell surface to surface, and 1cm apart.
Now there is a repulsion force between them.

Let me say there is a transformer which is charging these sheets. The transformer transform 240V AC up to 100kV DC (rectified).

If I now take those sheets and change the distance between them periodically. How will this change affect the current that flows through the transformers primary winding?

What happens to the transformer if one of the sheets approach ground which it is electrically attracted to?

Vidar
 
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The PSU is maintaining the PD between the sheets and the ground?
Why would there be a current flowing through the transformer to do that?

The changing force affects whatever is holding the sheets in position.
 
OK. Thanks. I assume then if one of the sheets is discharged to ground, it would affect the PSU, but not as the charge is constant.

I follow up question:

What if the ground is also a sheet, but with positive charge. If that sheet comes in between the two other negatively charged sheets, what will happen with the force between the two negatively charged sheets?
Will it remain the same but partially counterforced by the positively charged sheet?

Vidar
 
If you attached one of the sheets to ground the PSU that supplies it would overload yes... it's a short-circuit.

I suppose two positive plates close to each other would need more effort to keep the charges there - is that what you were thinking? But if the charges aren't moving, there's no current.

You can do all this without the PSU you know - just charge the sheets and don't let them discharge.

If the ground were also a sheet as described that you have two parralell-plate capacitors with a PSU maintaining the voltage between their plates. The net force experienced by each of the original (negative) sheets would be reduced though the force due to one sheet by the other one would remain the same.

You can also have fun with a parallel sheet capacitor using a PSU to maintain a constant voltage between them - then move the plates around and watch what happens on a galvinometer.
 

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