# Could Somebody help me please? EMF in parallel

Drakon25th
Ok, the question says: "Find the magnitudes and directions of the current through the 22 ohm and 15 ohm resistors (the internal resistance of the batteries is negligible)"

My question is how do i determine this if there's a second emf in the problem?

here's a picture of the problem:
picture

i tried using Kirchoff's loop law at first, first determining these two formulas:
0=E1-I1R1-I2R2
=9.0 - 22I1 - 15I2
I1 = .41 - .68I2

and

0=E2 - I2R2
= 6-15I2
I2 =.40

The problem is the second equation doesn't incorporate I3, so i cant use I3 = I2 + I1, so I'm stuck here.
Then I thought about using Ohm's law, but I am not sure how do i use E1 in terms of the parallel circuit to determine the total current going through the whole circuit. Please help me someone

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Drakon25th
by the way, the directions for I1, I2, and I3 in the picture are my predictions on the current flow throughout the circuit

Drakon25th

Janitor
I'm no electrical engineer, but...

It seems to me that given your choices for current flow (and I am presuming you are using conventional current, which imagines that a positive charge is what is flowing), your first equation has a bogus sign and should be:

0=E1-I1R1+I2R2.

Does it help to write another equation based on the third path of flow? That is the one with the two batteries and R1 in it:

E1+E2=I1R1.

That would allow you to immediately solve for I1. Then You could put that value in my corrected version of your first equation and solve for I2.

Last edited:
Drakon25th
so there would be no I3?

Janitor