What are the Unknown EMF and Currents in this Kirchhoff's Circuit?

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The discussion focuses on solving for unknown electromotive force (emf) and currents in a Kirchhoff's circuit with a resistor value of 3.48 ohms. The user has set up equations based on Kirchhoff's laws but is struggling to find the correct values for the currents and emf. They have outlined their equations for both the left and outside loops, applying the junction rule at a central junction. Despite their calculations, they believe their current value for I1 is incorrect and are seeking assistance in identifying their error. The conversation highlights the importance of accurately applying circuit laws to solve for unknowns in electrical circuits.
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Homework Statement



http://img207.imageshack.us/img207/1685/p1854altco4.gif

Find the unknown emf and the unknown currents in the circuit below, in which R = 3.48 . Take the positive direction for current flow in each branch to be upwards.
EMF = V
left branch= A
right branch= A


Homework Equations



Kirchhoff's circuit laws

The Attempt at a Solution



I added current lines to the diagram. Note that a coordinate system is imposed and all positive charges point up ( I guess this makes grading easier). I sketched the lines of current as best I could.

Here are my equations:

Left loop:

1.00v-3.48I1-E+(.05*2)

Outside loop:

1.00v-3.48I1-1.00I3+1.20V+4.00I3=0 (edit: caught a mistake here, last term should have been positive)

Apply junction rule to top center junction:
I1+.05=I3

Combine terms:
1.00v-3.48I1-E+.1=0
2.20v-3.48I1+3.00I3=0

Substituting I1+.05 for I3:

2.20v-3.48I1+3.00I1+.15=0

Combining like terms:

2.35-.48I1=0

I1(the left loop)=4.90A which is wrong.

Any ideas where I messed up?
 
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Where is the circuit diagram?
 
coolram80295 said:
Where is the circuit diagram?

Blast from the past! I have since moved past physics and on to medicine so things worked out well enough I suppose.
 
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