Questions tagged [nodal-analysis]
A circuit analysis method in which Kirchhoff's circuit laws are used to determine the voltage between all nodes (points where circuit elements connect) and the current through all elements. Always using in conjunction with the "circuit-analysis" tag.
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Determine Thevenin's equivalent circuit
I am doing my first year of engineering and have EE as a compulsory course. My teacher recently gave this question in an exam. He gave me a 5/10. He is not answering anybody's doubts. Can anyone tell ...
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How can same points have different current?
Aren't B and D the same point and shouldn't it actually be (B and B)?
If they aren't the same point what should be the current from B to D?
Why is it 2 amperes (from the answers) and not 10 amperes as ...
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Can't find error in nodal analysis
For the following circuit I did node analysis in order to find the greatest possible power at R and ended up with the equations (using node analysis):
$$n_1:\frac{v_1-V}{R_1} + \frac{v_1}{R_2} = 0$$
$$...
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What is the value of the current (i) and what is the right way to do it? [duplicate]
What exactly went wrong with the below method?
Here, in the same circuit I am getting a different value for the current in the mid wire only by rearranging the circuit.
I was trying to solve this ...
user208474
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Determine the nodal voltages in the circuit
This is a practice question from book: Engineering circuit analysis / William H. Hayt, Jr., Jack E. Kemmerly, Steven M. Durbin. — 8th ed. (pag. 91) .
Determine the nodal voltages in the circuit:
Ans:...
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Find current 'i' using Nodal Analysis
Here I know how we apply nodal analysis, but can somebody explain how can we calculate the current 'i' if there is no resistor in that particular wire?
I have shown my approach and working so far. I ...
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How to find V1 and V2 using Nodal Analysis?
I would like to use Nodal Analysis to find the power absorbed by 2 Ω resistor, V1, V2, and V3. For V3, it clearly shows that it is -24V. I would like to ask is V1 the same as Vy, or they are different ...
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Why do I read 20 microamperes instead of 5?
I am trying to do this experiment, but I can't read the current Ib. Note that the multimeter I use in this experiment is very sensitive. I don't know much about BJT transistors, so it might be an ...
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Nodal Analysis - Kirchoffs Current Law
Hello, I am stumbling across an issue here. So in Nodal Analysis, we identify our reference point and label the voltage nodes. Then we use KCL to find out equations and solve. My book is providing an ...
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RC Circuit Analysis Direction Changes Formula
In my Circuit Theory lesson, we were studying RC circuits and there was a question which I tried to make before our senior but I accidentally came up with a different answer due to choosing current ...
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Basic nodal analysis question
I have a question about node analysis method. The part I could not solve is the Node c's equation. In equations, C is represented by 3.Here is my question what is G5(i=GV) in the circuit. The empty ...
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Nodal voltage analysis in a DC circuit
I am trying to analyze the circuit given below:
The reference node is in the bottom with 0 V.
At nodes A and B writing down Kirchhoff’s first law equation trying to express each current in terms of ...
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Intuition on Thevenin's Theorem
In the following lecture by Prof. Anant Agarwal at 36:00, he intuitively proves Thevenin's Theorem using the following circuit
simulate this circuit – Schematic created using CircuitLab
If ...
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How to find the nodal voltage when there is a voltage source across two nodes?
How to find the nodal voltage when there is a 40V across Node 1 & 3?
V1= 22.4 V
V2= 65.6V
V3= 62.4 V
My Nodal Analysis
Node 1 (SuperNode):
-V1/4 - V1-V2/3 + V2-V3/2 - V3/6 = 0
Node 2
V1-V2/3 + ...
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Circuit analysis: connecting positive terminal of battery to reference node
In the circuit given below, how can I apply KVL to the loop on the right side? The reference node being connected to the positive terminal seems wrong.
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What is the op-amp output voltage for a voltage-controlled current source?
I am trying to analyse the voltages in a voltage-controlled current source.
What I have so far:
Vin = V_C
V_B = Vsupply - I_shunt*R_load
However, I don’t know how to find an equation for the op amp’...
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LTSpice outputting the incorrect voltage reading?
I have analysed this circuit by hand using both mesh and nodal and always come to the same voltage reading. However, when I simulate it in LTSpice, it does not match.
The V1 node reading should be 9....
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Strange Nodal Analysis
I have done the nodal analysis for the following question, and everything appears to have been done correctly as far as I can see. However, when I simulate the results I get values for the circuit ...
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Question about nodal analysis with an ideal op amp circuit
Iam trying to do nodal analysis of this op-amp circuit, but iam not quite sure if I have done it correctly or if I have missed something. The op-amps are considered being ideal so there is no current ...
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Where did this useful matrix decomposition come from for Nodal Analysis?
Background
The equations formed when finding the nodal voltages of a circuit can be expressed using nodal analysis as a square system matrix \$\mathbf{S}\$ (lets say \$m\times m\$ where \$m\$ is the ...
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Nodal analysis -> transfer function -> step response
I've been trying to get the transfer function for the circuit in the image below, but I seem to be doing something wrong, since the simulation on Circuitlab gives me a different Bode plot and I can't ...
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Nodal and Mesh analysis
I need to find the currents on each resistor of this circuit:
Where \$\beta\$ is a constant with units of resistance. Applying Kirchhoff's laws the equations are:
$$
I_1+I_3-I_2 = 0
$$
$$
V_0-I_1R_1-...
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Supernodes and KCL
Lets talk about Colpitts oscillator again (or the very basic circuit theory if you want). Suppose I modeled circuit as on the schematics below
I am interested in systematic ways of obtaining circuit ...
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Nodal analysis in s-domain help
I am learning circuit analysis in s-domain from my textbook "Engineering Circuit Analysis by William Hayt, 8th Ed". I am struggling with the mesh and nodal analysis.
In the book at page 583, there is ...
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Thevenin Theorem Problem
I am struggling to find the thevenin equivalent voltage for the following circuit. I attempted using source transformation and mesh analysis by initially transforming the current sources into voltage ...
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Trouble understanding how dependent current sources affect a circuit (Two-port networks)
While reviewing a problem from my recent test on two-port networks I noticed that it made its way online.
When someone was explaining the solution they utilized a point that I just completely missed. ...
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Nodal analysis for dependent voltage source
I want to apply nodal analysis at the red marked node of the above circuit. Here is my equation :
$$0.2v_0 - i_0 - 5 + \frac{v_3}{40} + \frac{v_3 - v_2}{10} = 0$$
My equation includes a supernode ...
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How does Kirchoff's current law work for sinusoidal voltage sources?
I was solving a steady state question with sinusoidal AC voltage source and the solution for the question used Kirchoff's current law to find the nodal voltage of a node. Now, I used to think that I ...
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Dependent voltage/current sources
I'm so sorry for that questions, but we need to understand what's going on behind the concept/theoretical of using device "dependent voltage/current source"!
My question: Yes, we are using dependent ...
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Where have I gone wrong with this nodal analysis calculation?
I am a bit confused as to where I have gone wrong in my nodal analysis calculation:
For the first node v1:
$$-3=(v1-v3)/2 +(v1-v2)$$
v2:
$$-(v1-v2)-(v3-v2)/4 = v2/3$$
v3:
$$7=(v3-v4)/5+(v3-v2)/4+(v3-...
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How do I solve the circuit below using nodal analysis?
I would like to know how I solve this circuit using nodal analysis
source
My attempt:
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Analysis of circuit with dependent voltage source with no apparent solution
This is an exercise from Irwin's book, 9th edition.
simulate this circuit – Schematic created using CircuitLab
Although the book calls for the use of nodal analysis, I decided to do it by mesh ...
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How would you solve this circuit with nodal analysis?
How would you solve this circuit with nodal analysis? I know it's the difficult route but it's a requirement. I understand that I need to create a super node that combines nodes a and b, and I have ...
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How to use nodal or mesh analysis with a current source?
This is my circuit:
The task is to get \$V_0\$ using Norton's theorem. My problem here is how current sources work.
I tried to use mesh analysis first, but didn't know how to.
Then I tried to use ...
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Mutual inductive coupling in a nodal admittance matrix
I have this question that has been haunting for quite a while now. To compute the nodal admittance matrix \$Y_N\$ of an electrical network, one can make use of the incidence matrix and the branch (or ...
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Joining two parallel branches with a wire
In the above circuit (grounding the negative terminal of the battery,) will the potential at C and D be the same?
According to my physics teacher, the potential is the same at the two points.
Why is ...
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Nodal Analysis Current Direction Matters
simulate this circuit – Schematic created using CircuitLab
I'm currently doing a question and it appears to me that the direction of the current matters.
For both the batteries I've assigned a ...
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Writing the Nodal and Mesh equations for large circuit and large supermesh
Here's my circuit:
simulate this circuit – Schematic created using CircuitLab
I have defined the node 'voltages' and the mesh current directions and the currents themselves. What I want to do ...
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Linear model of diodes for mesh current and nodal voltage analysis?
If we use the piecewise linear model for diodes, can we apply mesh current and nodal voltage analysis to a circuit containing a diode?
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Supernodes with Constant Current & Voltage Sources: Voltage = Current
I am a technologist trying to improve my understanding of electricity by reading a textbook. I am reading Fundamentals of Electric Circuits and something that keeps popping up when solving the ...
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How to do this nodal analysis problem with voltages sources plus a series resistance
I don't know what I am doing wrong, but it seems I got every number close to the answer but not the answer itself.
Here is the circuit:
For my first try I took the top node as V1 and the bottom as ...
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Nodal analysis with LEDs
How does nodal analysis work if I have not only resistors but also LEDs in my circuit?
Do I then have to convert the LEDs to resistors somehow?
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Nodal admittance matrix of a winding
I have a question concerning the nodal admittance matrix of a winding that has n turns.
If each turn of the winding had its own model, is it possible to consider my winding a n-port network?
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Dependent source circuit find voltage
Suppose we have this circuit
simulate this circuit – Schematic created using CircuitLab
How to do nodal analysis for this circuit?
Is it $$5-\frac{5-V_{A}}{2}-V_{A} = 0$$?
or $$5-\frac{5-V_{A}}{...
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How do I calculate the K for the dependant source using nodal analysis?
The question has provided power supplied by the voltage source and Vab = -3.6 V.
I had tried several ways but still can't solve it.
Below is the solving steps I tried:
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Utility of Node Analysis in Designing Circuits Step-by-Step
Question: Does node analysis have any utility when designing a circuit step-by-step, or must the entirety of the circuit be known before node analysis is useful? Here's an example to illustrate what I ...
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Node Method vs Simple KVL and KCL Equations Difference
I am just quite confused when deriving some equations for this simple circuit. Using just KCL and KVL (loops in green) to the best of my understanding, I get the first set of equations.
Firstly, are ...
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Performing small signal ac analysis with non-linear components
I have written a circuit simulator that uses Kirchoff's voltage and current laws to solve linear circuits containing capacitors, resistors, inductors and op-amps (where the op-amps are assumed to be ...
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Nodal question with current-controlled voltage source connected to independent voltage source
so i've got a question here
the question is to calculate v1 & iΦ, of course for nodal analysis (v1/24) + ((v1-(60+6iΦ))/3) + ((v1-va)/2) = 0, but (with va as the node left of 2 ohm resistor) how ...
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How to solve a circuit network involving a resistor parallel to a voltage source using only nodal analysis?
I have been stuck on this for the past week and this week i just dont seem to find out what am i doing wrong. Please help me spot my mistake. Here you can find My circuit on multisim. Please provide ...
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