Solve Currents in I3, I2, and I1

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The discussion focuses on solving for the currents I1, I2, and I3 using loop equations derived from circuit analysis. The user has set up three loop equations but is advised that the third equation is redundant as it is a sum of the first two. Additionally, it is pointed out that the junction rule, which accounts for the conservation of current at junctions, has not been applied in the user's approach. The importance of using both the loop and junction rules for accurate analysis is emphasized. The conversation highlights the need for correct application of circuit laws to find the desired currents.
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Homework Statement



find the current in I3 and I2 and I1

Homework Equations


junction Rule


The Attempt at a Solution


Loop 1 : -I1(4.1) + 29V - I1 (3.3) -I3(2.9)
-I1(7.4) -I3(2.9) = -29V

Loop 2 : I3 (2.9) - I2 (5.5) +16 V - I2(2)
-I2(7.5) + I3(2.9) = -16 V

Loop 3 : -I1(4.1) + 29V - I1(3-3)-I2(5.5) +16V-I2(2)
-I1(7.4)-I2(7.5)=-45V

Please help ASAP thanks!
 

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itryphysics said:

Homework Statement



find the current in I3 and I2 and I1

Homework Equations


junction Rule


The Attempt at a Solution


Loop 1 : -I1(4.1) + 29V - I1 (3.3) -I3(2.9)
-I1(7.4) -I3(2.9) = -29V

Loop 2 : I3 (2.9) - I2 (5.5) +16 V - I2(2)
-I2(7.5) + I3(2.9) = -16 V

Loop 3 : -I1(4.1) + 29V - I1(3-3)-I2(5.5) +16V-I2(2)
-I1(7.4)-I2(7.5)=-45V

Please help ASAP thanks!

Hi itryphysics! :smile:

(The third equation gives you no extra information …

it's just the sum of the first two equations …

the number of independent loop equations is the same as the number of independent loops. :wink:)

You've headed this "junction rule", but you haven't used the junction rule, only the loop rule.
 
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