Finding the potential across capacitors in capacitor-only circuits

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Gourab_chill
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Homework Statement
I have been asked to find the potential difference between points M and N in the given figure. The circuit is in the attachment.
Relevant Equations
Q=CV
I tried to attempt it by applying KVL to both the loops.
Circuit schematic of two loops sharing branch MN, with capacitors C1 and C2 and two batteries of emf E; charges Q, -Q, Q1, -Q1 and -(Q - Q1) labelled on the plates, with loop arrows (1) and (2).

I tried to find a possible charge distribution for the capacitors. I guess this is right.
Two typed equations. First: E = ((Q − Q1)/C1) − Q1/C2. Second: E = Q/C2 − Q1/C2.

On solving I get:
Handwritten-style equation: Q1 = E C2 (C2 - C1) / C1, with Q1 on the left and the fraction bar over C1.

from what I know potential difference between M and N is Q1/C2
but the solution is given as:
Equation V_MN = |E((C2 - C1)/(2C2 + C1))|, with V_MN on the left and an absolute value bar enclosing E times the fraction (C2 minus C1) over (2C2 plus C1).

Where am I wrong?
 
Attachments
  • Circuit schematic of a rectangular loop with capacitors C1 and C2 on the top wire, a middle branch from node M to node N containing capacitor C2, and batteries labelled E on the bottom wire.
    ques.PNG
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Welcome to PF!

You have a sign error in one of your first two equations.
 
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TSny said:
Welcome to PF!

You have a sign error in one of your first two equations.
thanks