Simple Circuit with Two Sources

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The discussion revolves around analyzing a simple circuit with two sources using Kirchhoff's Current Law (KCL) and Kirchhoff's Voltage Law (KVL). The calculations show that the current through the right source is zero, suggesting it is irrelevant to the circuit as drawn. It raises the question of whether this could have been predicted initially, with some participants noting that hindsight makes it easier to see the simplification. The voltage across the 4kΩ resistor is confirmed to be 4 Volts when the right source is removed. Overall, the conversation highlights the importance of circuit analysis and the potential for simplification in certain scenarios.
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Homework Statement


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Homework Equations


KCL and KVL

The Attempt at a Solution


The sum of the currents at the top node equals the current out through the middle
(Call ##I_1## the current from the left and ##I_2## the right)

##I_3 = I_1+I_2##

And the sum of the voltages around the loops equals 0.

##-I_3(4k)-I_1(6k) + 10V = 0##

##-I_3(4k) + 4V = 0##

The system of equations yields solutions
##I_3 = 1mA##
##I_1 = 1mA##
##I_2 = 0##

Now, it appears that either I made a mistake, or there is zero current going through the source on the right. Is it logical to conclude that the source on the right is irrelevant to the circuit?
 

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No mistake. Well, irrelevant to the circuit as drawn, yes; if other components were added it would likely come into play.
 
Could I have predicted this from the start, and crossed off the right side source, and solved for just a single source with series resistors?
 
showzen said:
Could I have predicted this from the start, and crossed off the right side source, and solved for just a single source with series resistors?
That's difficult to say.

You might have noticed that removing the right side source & leaving that branch open would give a simple series circuit with the voltage across the 4kΩ resistor being 4 Volts.

That's not something one would normally look for.

Hindsight is wonderful.
 
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