Complex circuits with Kirchoff's law

Thread starter serverxeon
Start date Feb 11, 2013
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Circuits Complex Complex circuits Kirchoff's law Law

In summary, Kirchoff's law, consisting of Kirchoff's current law (KCL) and Kirchoff's voltage law (KVL), is a fundamental principle used in circuit analysis. KCL states that the sum of currents entering a node must equal the sum of currents leaving that node, while KVL states that the sum of voltage drops in a closed loop must equal the sum of voltage sources in that loop. These laws are applied to complex circuits by identifying loops and branches and solving a system of equations to find unknown currents and voltages. Kirchoff's law can also be used for circuits with non-ideal components, but this may complicate calculations. Simplifications, such as assuming zero internal resistance for voltage sources

Feb 11, 2013

serverxeon

I have the diagram on the right,

I've set up a few equations to solve...

My calculator tell me mathematical error. can someone point out the error? thanks.

http://img21.imageshack.us/img21/5395/imgyqc.jpg

Last edited by a moderator: May 6, 2017

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Feb 11, 2013

ehild

Homework Helper

You have to input the value of the emf. The node equations are not independent. ehild

FAQ: Complex circuits with Kirchoff's law

1. What is Kirchoff's law and how does it apply to complex circuits?

Kirchoff's law, specifically the Kirchoff's current law (KCL) and Kirchoff's voltage law (KVL), are two fundamental principles in circuit analysis. KCL states that the sum of currents entering a node (or junction) in a circuit must equal the sum of currents leaving that node. KVL states that the sum of voltage drops in a closed loop must equal the sum of voltage sources in that loop. These laws are used to analyze and solve complex circuits.

2. How do I apply Kirchoff's law to a circuit with multiple loops and branches?

To apply Kirchoff's law to a complex circuit, you must first identify all the loops and branches in the circuit. Then, for each loop, you can apply KVL by setting the sum of voltage drops equal to the sum of voltage sources. For each node, you can apply KCL by setting the sum of currents entering the node equal to the sum of currents leaving the node. This will result in a system of equations that can be solved to find the unknown currents and voltages in the circuit.

3. Can Kirchoff's law be applied to circuits with non-ideal components?

Yes, Kirchoff's law can be applied to circuits with non-ideal components, such as resistors with non-zero internal resistance or capacitors with non-zero leakage current. However, in these cases, the calculations may become more complex as the non-ideal behavior of the components must be taken into account.

4. Are there any simplifications or approximations that can be made when using Kirchoff's law?

Yes, there are a few simplifications or approximations that can be made when using Kirchoff's law. One common simplification is to assume that the internal resistance of a voltage source is zero, which allows for easier calculations. Another approximation is to assume that the resistance of a wire is negligible, which is often valid for low-frequency circuits.

5. What are the limitations of Kirchoff's law?

Kirchoff's law is based on the assumptions of conservation of charge and energy, and it is only applicable to circuits in steady-state conditions. Additionally, the laws assume linear behavior of components, so they may not be accurate for circuits with non-linear components. Kirchoff's law also does not take into account electromagnetic interference or parasitic effects, which may affect the behavior of a circuit in real-world conditions.