Finding energy stored in capacitors without solving for current

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Homework Statement



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Long time after closing K1,k2 and k3 the energy stored in each capacitor is?


The Attempt at a Solution



My method is to find out an expression for the current through the capacitor (of net capacitance 2C) at any time t and use I = CdV/dt to find out V across it at t=inf.

However this method appears to be very long. Is there any shortcut?
 

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Yes. At T=inf the current through the capacitors is zero.
 
Antiphon said:
Yes. At T=inf the current through the capacitors is zero.
Also notice: that will leave you with a fairly simple circuit. The capacitors in combination with R3 are in parallel with R2[/SUB, but the voltage drop across R3 is zero since there is no current through it.
 
So you mean voltage drop across any capacitor is V ?
 
Abdul Quadeer said:
So you mean voltage drop across any capacitor is V ?
No.

As t → ∞ :

The only current flowing is through R1 and R2.

What is the voltage drop across R2?
 
Its V/3
Thank you!
 
Abdul Quadeer said:
Its V/3
Thank you!
Correct !