How to find the charge on each capacitor

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Homework Statement


Two batteries are connected to two identical capacitors X and Y.Initially all the plates of the capacitors are uncharged.How to find charge on each Capacitor in the given diagram.Let the Capacitance of Capacitor be C.
IMG_20180131_130237.jpg

Homework Equations


1.Q=CV
2.Kirchoff's law
3.C=C1+C2 ( Equivalent Capacitance for capacitors in parallel connection)
4.E=E1+E2(Equivalent emf for cells in series)

The Attempt at a Solution


I thought that there will be no charge on Y Capacitor as it is connected to negative terminal from both sides of 0 potential.
Q(on X)=CV( across X i.e.=3V)
Therefore Q=3C. But this answer is wrong. What is wrong in my approach?
 

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Fara_k2 said:
I thought that there will be no charge on Y Capacitor as it is connected to negative terminal from both sides of 0 potential.
Q(on X)=CV( across X i.e.=3V)
What would that mean for the charges on the upper plates in both capacitors? What would that mean for the total charge in the upper half of the circuit? Where would this charge come from?

In general you can't know the potential of a battery terminal without analyzing the circuit. All you know for sure is the difference between the terminals.
 
Think about Conservation of charge as well as energy on the system .Then you may be able to solve this
 
Fara_k2 said:

Homework Statement


Two batteries are connected to two identical capacitors X and Y.Initially all the plates of the capacitors are uncharged.How to find charge on each Capacitor in the given diagram.Let the Capacitance of Capacitor be C.
View attachment 219422

Homework Equations


1.Q=CV
2.Kirchoff's law
3.C=C1+C2 ( Equivalent Capacitance for capacitors in parallel connection)
4.E=E1+E2(Equivalent emf for cells in series)

The capacitors are not connected in parallel. They are in series, like the cells, in the same loop.

Fara_k2 said:

The Attempt at a Solution


I thought that there will be no charge on Y Capacitor as it is connected to negative terminal from both sides of 0 potential.
Q(on X)=CV( across X i.e.=3V)
Therefore Q=3C. But this answer is wrong. What is wrong in my approach?
The capacitor Y is connected to the negative sides of two batteries, but it does not mean that that those negative terminals are at the same zero potential.