Beginning circuits. Need an answer.

Thread Starter


Joined Jul 5, 2007
Hi all,

This one should be a breeze to those of you with experience. I'm reading the ibiblio online textbook on DC Circuits ( and keep going crosseyed over this circuit, mainly because I don't get how it makes a functioning circuit. Here's the pic.

I'm in the process of measuring voltage drops and proving Kirschoff's Voltage Law, etc.... but where I'm getting hung up is in understanding how the electrons actually flow around this circuit. I could use a little help.

I "get" that they are two series circuits, joined by a wire, but when I trace electron flow from the 35V battery, through 7, then 8, wouldn't that "crash" into the electrons from coming from points 4, 9 on the 25V battery side?

Thanks in advance....


Joined Apr 27, 2007
Well, you have to think about this circuit as two separated circuits. The common wire shared by the two batteries is only there to keep their respective negative sides at the same potential. Think it as a common ground. There is no electron flow from points 8 to 9, and therefore points 7, 8, 9 and 10 are at the same potential.
Given that, I think it is simple to find out the potential difference between any points in the circuit.


Joined Apr 2, 2007
solve them as separate circuits, no current flows from one to another as no return path for electron is if u have any further queries .