Solving a Superposition Circuit Question: Finding Ia without a Voltage Source

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andyintranzit
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http://img442.imageshack.us/img442/2070/circuit1vf1.gif

i drew this from a superposition question.. the voltage source is shorted out.

what on Earth could Ia be if there's no voltage source?
 
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wow I am really stupid. you have to solve for only one voltage/current source at a time, right?

just out of interest though... is it possible to solve that?
 
andyintranzit said:
wow I am really stupid. you have to solve for only one voltage/current source at a time, right?

just out of interest though... is it possible to solve that?
Of course you can solve it by using superposition. Otherwise, you can solve it using Kirchoff's and Ohm's laws.
Call V1 the voltage between resistors 3 and 5 ohm and V2 the voltage between 5 and 2 ohm. Call ib the current in the 3 ohm resistor and ic in the 2 ohm. You have:
ib = -V1/3
ic = V2/2
ia = (V1 - V2)/5
ib = ia + 6
ic = ia + 8
You have 5 independent equations in 5 unknowns. You can solve it for the unknowns.