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mhrob24
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*If at any point I say something incorrect or its clear I don't have the right understanding of something, please point it out and correct me. I need to be sure I'm understanding it all correctly. So please don't answer unless you're willing to read this entire post*
So I know capacitors in series have same the charge (Q) stored on each of their plates because of conservation of charge (the magnitude of the charge moved through the circuit across the battery terminals must be conserved so as the charge travels, each conducting capacitor plate with have the same magnitude charge Q). I also know that its possible that the potential between each capacitor is different. My book doesn't directly explain why after stating this, but I can see how that's possible :
V = Q/C
When doing the calculation for capacitance between 2 parallel plates, we get: C = ε0*A/D. Thus, for parallel plate capacitors (or any other type of capacitor for that matter), the capacitance only depends on the geometry (area) of the conducting plates and the distance between them. So, you can effectively change the voltage of a capacitor without messing with the magnitude of charge on the plates because capacitance is independent of Q (and also of V). So that makes sense to me. So not all the capacitor plates in a series will have the same area or distance between them, but they will all have the same magnitude Q stored.
What DOESN'T make sense to me is the fact that each capacitor connected in parallel will have the same V across their plates, but at the same time, its also possible that each capacitor stores a different charge.
So the voltage in our case is basically the work done in moving a charge in an electric field divided by the charge's magnitude. So, the voltage depends on the electric field, not the charge moving in it. So when we look at a capacitor connected in parallel, we know that the charge Q stored on its set of plates could possibly be different from the charge stored on another capacitor within the parallel connection. With that said, the electric field DOES depend on the charge stored on the capacitor (that's what causes the uniform field between the plates in the first place). So, this means that the electric field between each capacitor in the parallel connection can't be the same if we know that its possible for the charge on one capacitor can be different from another capacitor. Thus, if the electric field on one capacitor can be different from another, and the voltage depends on the electric field, how can each capacitor have the same V?
So I know capacitors in series have same the charge (Q) stored on each of their plates because of conservation of charge (the magnitude of the charge moved through the circuit across the battery terminals must be conserved so as the charge travels, each conducting capacitor plate with have the same magnitude charge Q). I also know that its possible that the potential between each capacitor is different. My book doesn't directly explain why after stating this, but I can see how that's possible :
V = Q/C
When doing the calculation for capacitance between 2 parallel plates, we get: C = ε0*A/D. Thus, for parallel plate capacitors (or any other type of capacitor for that matter), the capacitance only depends on the geometry (area) of the conducting plates and the distance between them. So, you can effectively change the voltage of a capacitor without messing with the magnitude of charge on the plates because capacitance is independent of Q (and also of V). So that makes sense to me. So not all the capacitor plates in a series will have the same area or distance between them, but they will all have the same magnitude Q stored.
What DOESN'T make sense to me is the fact that each capacitor connected in parallel will have the same V across their plates, but at the same time, its also possible that each capacitor stores a different charge.
So the voltage in our case is basically the work done in moving a charge in an electric field divided by the charge's magnitude. So, the voltage depends on the electric field, not the charge moving in it. So when we look at a capacitor connected in parallel, we know that the charge Q stored on its set of plates could possibly be different from the charge stored on another capacitor within the parallel connection. With that said, the electric field DOES depend on the charge stored on the capacitor (that's what causes the uniform field between the plates in the first place). So, this means that the electric field between each capacitor in the parallel connection can't be the same if we know that its possible for the charge on one capacitor can be different from another capacitor. Thus, if the electric field on one capacitor can be different from another, and the voltage depends on the electric field, how can each capacitor have the same V?