Three plate capacitor and charge distribution

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aashutosh
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In the figure given the capacitance for the two pair would be same. Can anybody please explain me how the charge would be distributed across each plate?
I think that the middle plate being isolated should have +Q on one side and -Q on other, but how would be the charge distribution about the remaining plates as both of them are connected to the positive terminal of the battery.
Circuit schematic of three parallel plates labelled A, B and C with a 12V battery; A and C connect to one battery terminal and the middle plate B is isolated between them.
 
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A and C are connected to the positive terminal of the battery and acquire positive charge. B is connected to the negative terminal and acquire negative charge.
 
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zoki85 said:
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A and C are connected to the positive terminal of the battery and acquire positive charge. B is connected to the negative terminal and acquire negative charge.
Circuit diagram of a 12V battery connected to three parallel capacitor plates labeled A, B and C, with plate A marked +Q on top and -Q below, plate B marked ?? on both faces, and plate C marked -Q on top and +Q below.
so will the charge distribution on the plates be as shown in the figure? If B is connected to the negative terminal then will both the sides of the plates will have -Q charge. But the pair of capacitor plates should have opposite charges right? Please i am a little confused with this. Correct me if i am wrong.
 
aashutosh said:
so will the charge distribution on the plates be as shown in the figure? If B is connected to the negative terminal then will both the sides of the plates will have -Q charge. But the pair of capacitor plates should have opposite charges right? Please i am a little confused with this. Correct me if i am wrong.

no, Plates A and C are positively charged and Plate B is negatively charged

Circuit diagram of three parallel metal plates labelled A, B and C, connected to a 12V battery with its positive terminal to the top plate A and bottom plate C and negative terminal to middle plate B. Plates A and C show +Q charges on their surfaces and plate B shows -Q charges.


Why would you expect it to be any different to this ?
you cannot get a excess negative charge on a plate connected to the battery positive ;)
Dave
 
Last edited:
davenn said:
no, Plates A and C are positively charged and Plate B is negatively charged

View attachment 78672

Why would you expect it to be any different to this ?
you cannot get a excess negative charge on a plate connected to the battery positive ;)
Dave
Ok thank you. I thought that the capacitor plates should have + charge on one side and - on other side. May be i got confused.
 
aashutosh said:
Ok thank you. I thought that the capacitor plates should have + charge on one side and - on other side. May be i got confused.

No Problems

Just consider that the negative charge on plate B is going to "drive off " ( repel) negative charges off plates A and C and thereby leaving them positively charged :)

Dave
 
keep up the learning and questions
studying and learning about electronics and its related physics will keep you going for a lifetime
I have been at it for 40+ years and there's still so much I don't know haha ... its just such a huge subject