I have the following circuit

                                enter image description here

in wich both batteries provide the same voltage and the capacitors are uncharged.

I need to find the current in each path of the circuit at time $t=0$ when i connect the batteries.

I know that at $t=0$ the charge of the capacitors is zero, so $V_c=\frac qC=0$, and when i apply the laws of Kirchhnoff over the circuit i can ingore them.

Then my circuit is

                                enter image description here

But... what's next?

Can i make an equivalent resistance? Because, i can't think of any.

If i want to continue with Kirchhnoff... In what direction does the current flow? And how does the potencial decrease/grows while passing throw each resistance?


closed as off-topic by FGSUZ, John Rennie, Bill N, Yashas, Kyle Kanos Apr 25 at 17:01

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Indeed, you must do this using Kirchhoff's laws.

The direction of the current is something that you can CHOOSE. Do not worry: if the current was flowing in the opposite direction, you'll get a minus sign when you solve it.

In other words, now you have to decide the reference direction for the currents, just like you choose where you put your origin of coordinates.

Just draw how currents could flow. Suppose that that is the way they flow. Then solve the circuit.

If your assumption was wrong, you will get a minus sign somewhere. That just means that you guessed wrong, but it does not matter, because the numerical value is correct. Only the sign can vary. The sign is telling you if the flow was in that direction or opposite.

Actually, what we are doing is a choice of references. "I set that currents will be positive rightwards, and negative leftwards". But this is only a reference. The currents will be unknown until you solve the whole system.


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