Mastering Capacitors: A Comprehensive Guide to Understanding and Troubleshooting

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    Capacitors
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Discussion Overview

The discussion revolves around understanding the behavior of capacitors in a circuit, particularly focusing on voltage differences, current flow, and the implications of connecting capacitors in various configurations. Participants explore theoretical scenarios and practical limitations related to capacitor discharge and circuit design.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant shares a link for others to identify faults in their understanding of capacitors and their behavior in circuits.
  • Another participant questions the feasibility of having a voltage across a resistor without current flowing through it, suggesting that this implies an infinite resistance.
  • A participant proposes that a device can add voltage to a capacitor without allowing it to discharge into the circuit, raising questions about the method to achieve this.
  • Concerns are raised about the implications of connecting charged capacitors in sequence, particularly regarding voltage summation and current flow when the circuit is closed.
  • It is noted that if a capacitor does not allow current to flow, it must have infinite internal resistance, leading to the conclusion that it cannot discharge.
  • Participants discuss the concept of charge distribution among capacitors and the impact of load on voltage levels, suggesting that energy loss occurs when work is done by the load.
  • A metaphor is used to illustrate the challenges of maintaining voltage levels while draining energy from the circuit, comparing it to shuffling water between bottles while losing some to a sink.

Areas of Agreement / Disagreement

Participants express differing views on the behavior of capacitors and the conditions under which they operate. There is no consensus on the methods to achieve the desired circuit behavior, and multiple competing perspectives remain unresolved.

Contextual Notes

Limitations include assumptions about ideal circuit conditions, the behavior of real components, and the definitions of voltage and current in the context of capacitors and resistors.

cala
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Hello everybody.

Can't surrender so much easy... Take a look to this:

www.geocities.com/k_pullo/suppose.htm

You know the process: tell where do you see the faults, and then i will understand somethings, but new doubts will come to my mind.

Thanks for all your support in physics, you're making a good job into my understanding, first on centrifugal-centripetal, then on magnets and finally into electrostatics. Will it be the end?... SURE NOT!
 
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Cala said:

"1 - You have some kind of device that makes 12 V voltage difference between two points, but no current can go through this device, so it never discharges. From the 12 V point you connect a 12 V charged capacitor, then a LOAD, and then two parallel 6V charged capacitors."


Then your resistor is under 6 v potential, right? Thus, the current I=6v/R is passing via loop - source and all capacitors. This contradicts to your requirement of "no current can go through this device".
 
What i mean is that the 12 V device force the capacitor to discharge through the load.

What i want the device to do is add voltage to the capacitor, but avoiding this capacitor to discharge to that part of the circuit. (keep the voltage, but without current allowed to flow).

I mean, the 12 V capacitor is not allowed to discharge into the device, but the device force the capacitor to see 12 V added to its internal 12 V, so it discharges to the right side, not to the left.

Is there not a method to put some point into 12 V without allowing any current going back?
 
How can you have non-zero voltage on a resistor and zero current via it? This simply would mean that the resistance is infinite (no resistor in your circuit, just open circuit (discontinuity) in this place).
 
1. Charged capacitors in sequence cause voltage on resistor to be sum: 24V
2. Current flows only when circuit is closed, same current must flow in both of left capacitors. If your leftmost capacitor does not offer current, its internal resistance is infinite, and no current will ever flow. You can't 'discharge' upper capacitor.
3. There is no source to recharge upper capacitor to 24V potential.
Add +/- signs to capacitors to better understand what happens.
4. Capacitors store charge. When you divide it to two capacitors, each will have half of it. Your rightside capacitors will have each half of charge. When you further use one of them to 'recharge' upper cap, it will again have half of that half. You loose charge, whatever you think of voltage games.
5. If your load does any work, there is no way you could get 12V on rightside capacitors. It will be less by amount of voltage drop over the load resistor.
You might get this thing to work for 2-3 cicles, but then it would be empty by any measure.

Finally, what you try is like take few bottles, try shuffling water around them in different ways, and hope to have same amount of water in bottles although draining some of it out to the sink (resistor)..
 

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