Theoretical electrodynamic cycle 2

In summary, when switches are opened and closed in a repeating fashion, the electrical energy stored in capacitors is lost.
  • #1
Ambforc
14
0
Here is a second thought experiment I designed to test if I understand certain concepts concerning electrostatics correctly. Help will be appreciated.

There must be an error somewhere in the explanation below; I am giving the explanation as if “factual” only to explain how I understand it at present.

Consider the setup shown in the figure for step 1. The potential difference source (cell V1) charged capacitor C1 to full capacity (voltage over capacitor equal to voltage over cell).

In step 2 switch S1 is opened, and S3 is connected next. Work is done on resistor R2 as charges separate between the plates to establish an opposing electric field so that the potential difference between the two conductive plates of capacitor C2 is zero.

Step 3 involves opening switch S3 and closing switch S2 afterwards. Work is done on resistor R1 as the current flows to equalize the charges on the plates of capacitor C1.

Step 4 is to close switch S3. Work will again be done on resistor R2 as the current flows to equalize the charges on the plates. Get back to step 1 by opening switch S3 and S2, and closing switch S1. The cell will do work to charge capacitor C1.

Assuming that there is no dielectric effect on capacitor C1 due to the charged plates of C2 in the middle of it (cannot see why there should be as the electric field due to the charged plates C2 is supposed to be zero to the left and right of capacitor C2), the work done in step 3 is equal to the work done on the cell to recharge capacitor C1 (assuming a fully efficient, reversible charging and discharging process on the capacitor). This leaves the work done on resistor R2 in steps 2 and 4 as excess from the cycle, something that is not supposed to happen.

I will appreciate a pointer as to what I overlook.
 

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  • #2
I have not received any reply to date, I assume that it has been overlooked by those who are able to answer it. Is it possible that this post is better suited for a different forum?
 
  • #3
It seems you assumed that the total charge on c1 is not influenced by the potential over c2 let met draw you a better pic of step 1 http://img40.imageshack.us/img40/7471/loledg.png .
Now you will see 3 caps , which is exactly the equivalent of your system.

step 2
here you open s1 and then close s3.
basically you discharge cap b through r2

step 3
here you open s3 and close s2
you discharge the remaining energy that was stored in cap a and cap b into R1.


Thus the total amount of energy lost is the sum of all the energies in all the caps. which means the is no gain of energy.


oh yeah i sent you a mail :}
 
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  • #4
Thank you, this makes it clear.
 
  • #5


Thank you for sharing your thought experiment with me. It seems like you have a good understanding of the concepts of electrostatics and are trying to apply them in a theoretical cycle. However, there are a few points that I would like to clarify.

Firstly, in step 2, when switch S1 is opened and S3 is connected, the charges on the plates of capacitor C2 will not necessarily be equalized to zero. It depends on the initial charge distribution on the plates and the resistance of resistor R2. It is possible that there will still be a non-zero potential difference between the plates of C2.

Secondly, in step 3, when switch S3 is opened and S2 is closed, the current will not flow through resistor R1 to equalize the charges on the plates of C1. Instead, it will flow through both resistors R1 and R2, as the charges on the plates of C2 will also contribute to the current flow. This means that the work done on resistor R1 will not be equal to the work done on the cell to recharge capacitor C1.

Lastly, in step 4, when switch S3 is closed, the current will flow through resistor R2 to equalize the charges on the plates of C2. This is not an excess from the cycle, as it is necessary for the cycle to continue and for the capacitor C1 to be recharged.

In summary, it is important to consider the initial charge distribution on the plates, the resistance of the resistors, and the contribution of charges from other capacitors in the circuit. I hope this helps to clarify any misunderstandings. Keep exploring and experimenting, and do not hesitate to ask for help if needed.
 

Related to Theoretical electrodynamic cycle 2

1. What is a theoretical electrodynamic cycle 2?

A theoretical electrodynamic cycle 2 is a mathematical model used to describe the behavior of electric and magnetic fields in a closed system. It is used to understand the interactions between charged particles and electromagnetic waves.

2. What are the main components of a theoretical electrodynamic cycle 2?

The main components of a theoretical electrodynamic cycle 2 include electric and magnetic fields, charged particles, and electromagnetic waves. These components interact with each other to create a continuous cycle of energy exchange.

3. How is a theoretical electrodynamic cycle 2 different from a theoretical electrodynamic cycle 1?

Theoretical electrodynamic cycle 2 builds upon the concepts and equations of theoretical electrodynamic cycle 1, but includes additional factors such as non-uniform electric and magnetic fields, and the effects of moving charged particles.

4. What is the significance of studying theoretical electrodynamic cycle 2?

Studying theoretical electrodynamic cycle 2 allows scientists to understand and predict the behavior of electric and magnetic fields in complex systems, such as in particle accelerators or space environments. It also has practical applications in the development of technologies such as wireless communication and electric motors.

5. How is theoretical electrodynamic cycle 2 applied in real-world situations?

Theoretical electrodynamic cycle 2 is applied in a variety of real-world situations, such as in the design and operation of particle accelerators, electric motors, and generators. It is also used in the development of wireless communication technologies and in understanding the behavior of electromagnetic waves in space.

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