Are My Equations Correct for Kirchoff's Rules?

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In summary, the conversation discusses equations and algebraic manipulation in a circuit problem. The loop 1 equation was incorrect and needed to be fixed, and the use of I references from the problem should be avoided. The correct node equation is I1 = I2 + I3.
  • #1
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My loop 1 equation is I1R1 + I2R2 + E1 = 0
simplified to: 4I1 + 2I2 + 28 = 0
Loop 2: I3R3 - E2 - I2R2 = 0
simplified to: 1I3 - 7V - 2I2 = 0

And my node 1 equation is: 0 = I1 + I2 + I3

So doing algebra.. I get my I1 to equal 7.. which doesn't match with the -5A for I1 as given in the problem.

Are my equations wrong? Or is my algebra wrong?
 

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  • #2
Loop 1 equation is wrong. No need to go further till that's fixed. I think you are trying to use the I references from the problem. Don't. Use only Iloop1 and Iloop2.
 
  • #3
Okay well I changed my node equation to I1 = I2 + I3 and got the right answer in the end.
 

What are Kirchoff's Rules?

Kirchoff's Rules, also known as Kirchoff's Laws, are fundamental principles in circuit analysis that are used to determine the voltage and current in a circuit. They are named after German physicist Gustav Kirchoff, who first introduced them in the mid-19th century.

What is Kirchoff's Current Law (KCL)?

Kirchoff's Current Law states that the algebraic sum of the currents entering and leaving a junction in a circuit must be equal to zero. In other words, the total current entering a junction must be equal to the total current leaving the junction.

What is Kirchoff's Voltage Law (KVL)?

Kirchoff's Voltage Law states that the sum of the voltage drops in a closed loop in a circuit must be equal to the sum of the voltage sources in that loop. In other words, the total voltage around a closed loop must equal the total voltage supplied by the sources in that loop.

How are Kirchoff's Rules used in circuit analysis?

Kirchoff's Rules are used to analyze and solve complex circuits by applying them to different parts of the circuit, such as individual loops or junctions. By using these rules, the voltage and current in each part of the circuit can be determined, allowing for a better understanding of the circuit's behavior.

What are some common applications of Kirchoff's Rules?

Kirchoff's Rules are used in a variety of fields, including electrical engineering, physics, and telecommunications. They are essential in circuit analysis and are used to design and troubleshoot electrical circuits, as well as in the development of electronic devices and systems.

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