Choosing a zero for potential for 2 batteries in parallel with capacitors

In summary, the question is about finding the charge and potential drop across each capacitor, which are in series. The student has tried applying Kirchoff's laws but is unsure about the direction of potential drop or rise and is getting different answers with different assumptions. They ask if this problem has multiple solutions and if they should show their working. The expert responds that there is only one solution and suggests following Kirchoff's laws in an anticlockwise manner. They also mention that the direction of current and net voltage in the circuit are important considerations. Lastly, the student clarifies that they want to solve for the steady state when the current is zero, but asks for guidance on how the current should flow to charge the capacitors.
  • #1
EddiePhys
131
6

Homework Statement


I want to find the charge and potential drop across each capacitor
IMG_20170814_154644_01.jpg

Homework Equations

The Attempt at a Solution



I know both the capacitors are in series and hence have the same charge on them. However I don't know how to calculate the potential drop across the capacitors. Tried applying Kirchoff's laws, but I don't know whether there is a potential drop or rise across each capacitor so I don't know which sign to use. Different signs are giving different answers. Is it possible that this problem has multiple solutions?
 
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  • #2
EddiePhys said:
Is it possible that this problem has multiple solutions?
No.
EddiePhys said:
Tried applying Kirchoff's laws, but I don't know whether there is a potential drop or rise across each capacitor so I don't know which sign to use. Different signs are giving different answers.
If you showed your working, we can see where you went wrong.
 
  • #3
cnh1995 said:
No.

If you showed your working, we can see where you went wrong.

If you apply Kirchoff's laws, say in an anticlockwise manner, the answer will depend on whether you assume the potential to drop or rise across either one of the capacitors or rise/drop across both capacitors
 
  • #4
EddiePhys said:
If you apply Kirchoff's laws, say in an anticlockwise manner, the answer will depend on whether you assume the potential to drop or rise across either one of the capacitors or rise/drop across both capacitors
What is the direction of current? What is the net voltage in the circuit?
 
  • #5
cnh1995 said:
What is the direction of current? What is the net voltage in the circuit?
I want to solve this when it's in steady state so the current is zero
 
  • #6
EddiePhys said:
I want to solve this when it's in steady state so the current is zero
Yes, but to charge the capacitors, how should the current flow?
 

Related to Choosing a zero for potential for 2 batteries in parallel with capacitors

1. What is the purpose of choosing a zero potential for 2 batteries in parallel with capacitors?

The purpose of choosing a zero potential for 2 batteries in parallel with capacitors is to ensure that the overall potential difference across the circuit remains constant. This is important because it allows for a stable and consistent flow of electricity through the circuit.

2. How do you determine the appropriate zero potential for 2 batteries in parallel with capacitors?

The appropriate zero potential for 2 batteries in parallel with capacitors can be determined by calculating the total potential difference of the batteries and capacitors. This can be done by adding the individual potential differences of each component and then choosing a zero potential that is equal to this total potential difference.

3. Can the zero potential for 2 batteries in parallel with capacitors be changed?

Yes, the zero potential for 2 batteries in parallel with capacitors can be changed. This can be done by adjusting the individual potential differences of the batteries and capacitors or by adding or removing components from the circuit.

4. What are the consequences of choosing an incorrect zero potential for 2 batteries in parallel with capacitors?

Choosing an incorrect zero potential for 2 batteries in parallel with capacitors can result in a fluctuation of the overall potential difference in the circuit. This can lead to an unstable flow of electricity and potentially damage the components in the circuit.

5. Are there any safety precautions to consider when choosing a zero potential for 2 batteries in parallel with capacitors?

Yes, it is important to ensure that the total potential difference of the batteries and capacitors is within a safe range for the circuit. It is also important to use proper insulation and handle the components carefully to avoid any potential hazards.

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