Help Me Find the Capacitance: A Stumped Student's Story

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The discussion revolves around a student's confusion regarding the arrangement of capacitors and their resultant capacitance. The student initially believed that two capacitors were in parallel while one was in series, leading to an incorrect calculation of 2C/3. However, the book indicates that all three capacitors are in series, resulting in a capacitance of C/3. Participants clarify that the student cannot ignore the end plates and emphasize the importance of understanding the points between which the capacitance is being calculated. The conversation highlights the need for clear reasoning in capacitor arrangements to avoid miscalculations.
cupid.callin
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Hi again!

I got stuck in this question (Pic), the original question is the fig. 1. I then arranged the charges on the plates (fig 2) and then separated the plates to form three capacitors. Now I just don’t know what the capacitance will be and how to find it!
First I thought to ignore the two plates at 2 ends. Then the two capacitors on right will be in parallal and their resultant in series with the last one… then answer comes out to be 2C/3 … which is wrong!
According to the book’s answer, all three capacitors will be in series, to get capacitance as C/3 …
Please tell me how are three capacitors in series, and can I really ignore the end plates!
 

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Please someone help!
 
They are not in series. Your equivalent circuit on the right is correct. Between which points do you need the resultant capacitance?

ehild
 
No, I am telling you they are in series because the net capacitance comes out to be (acc. to book) C/3
 
some help?
 
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