Question about high electric charge.

AI Thread Summary
The discussion revolves around the behavior of two highly charged sheets with the same polarity and their interaction with a transformer. When the distance between the sheets is altered, it affects the force between them, but does not directly impact the current flowing through the transformer's primary winding unless one sheet is discharged to ground, which could overload the power supply. If a positively charged sheet is introduced between the negatively charged sheets, it partially counteracts the repulsive force between them. The conversation also highlights that maintaining a constant voltage between the sheets can be achieved without a power supply, as long as the charges remain static. Overall, the dynamics of electric charge and force interactions in this setup are central to the discussion.
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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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