Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [thevenin]

Thévenin's theorem for linear electrical networks to simplify the analysis of complex electrical circuits.

561 questions
20
votes
3 answers

I think I found an error in an electronics book. Are my equations correct here?

I'm reading Practical Electronics for Inventors, 4th edition, to freshen up my long forgotten knowledge of electronics. I love the book so far, but I just came across an equation there which seems incorrect. I don't want to immediately assume that…
bnorb
  • 303
  • 1
  • 5
12
votes
3 answers

Help me solve this DC circuit problem

The circuit looks like this: All the elements are known, except for \$I_{g2}\$. \$E_1=3V,E_4=10V,E_6=2V,E_8=1V,E_9=4V,I_{g7}=1mA,\$ \$R_1=1k\Omega,R_2=1k\Omega,R_3=1k\Omega,R_4=2k\Omega,R_5=4k\Omega,R_6=3k\Omega,R_9=6k\Omega\$ But we also know the…
A6SE
  • 379
  • 1
  • 8
  • 24
9
votes
2 answers

How to find the Thévenin voltage?

How do I find the Thévenin voltage in this diagram? In parallel the voltage remains the same, so should it be 10 volts across AB? I am given that since \$R_3\$ and \$R_4\$ are not connected on one end, they do not carry current. Therefore, they…
user1799
8
votes
3 answers

Why is the voltage drop across this 1 ohm resistor being neglected in this practice problem? (Thevenin's Theorem)

We are given the following circuit and told to calculate the equivalent voltage of everything to the left of the a and b terminals: It omits the load resistor and lays the circuit out as such for mesh analysis: It claims that voltage across…
Sam D20
  • 469
  • 1
  • 6
  • 12
6
votes
4 answers

How does this trick to finding the Thevenin Resistance work?

Here's a circuit for which I was asked to find the Thevenin Resistance: My professor said that there's a shorter way to do this. Apparently one could short-circuit voltage sources(in this case the 72 V source) and replace current sources by an open…
lazearoundallday
  • 165
  • 6
6
votes
1 answer

Why is the verification of Thevenin's theorem more accurate than that of Superposition theorem?

In my first course on Electrical Engineering, we have an experiment in the Electrical lab that asks us to verify the Thevenin theorem and the Superposition theorem and cross-check our results with our calculations on paper. Here are the circuit…
William R. Ebenezer
  • 165
  • 3
  • 10
6
votes
1 answer

LM324 op-amp wheatstone bridge amplifier formula

I'm planning to use an LM324 opamp as a signal amplifier for a cell load (strain gauge in a Wheatstone bridge). This particular application is shown in the datasheet (see image). It shows the Wheatstone brige (bottom-left resistor is the strain…
dodod
  • 137
  • 1
  • 9
6
votes
4 answers

Trouble finding Thévenin equivalent for this circuit

I'm having trouble finding the thevenin equivalent for this circuit To solve this problem, I changed the voltages from 20V and 5V to 25V and 0V as shown below My resulting output voltage is 10V and the Thévenin resistance is 6K ohms. Now the…
goli12
  • 139
  • 1
  • 2
  • 8
5
votes
1 answer

Thevenin equivalent with dependent source

Well, I'm trying to find the Thevenin equivalent of this circuit: As you can see, the only current source is a dependent source. However, the control variable is in a wire where, if nothing is connected between A and B, is \$i_\Delta = 0\$ A, and…
Victor Buendía
  • 155
  • 1
  • 6
5
votes
2 answers

Maximum power transfer

I have problems to solve the next exercise about maximum power transfer. I know that potentiometer has two internal resistors. In this exercise, I must find the \$R\$ value to transfer maximum power to \$R_{L}\$. Now, I have two ideas: To consider…
Chuz
  • 297
  • 2
  • 3
  • 14
5
votes
1 answer

What is the Thévenin equivalent of the mains power supply?

Thévenin's theorem says that any voltage source can be modeled as an ideal source in series with some complex impedance. How does one quantify this model for AC mains supplies? What parameters are relevant? And are there any broad assumptions that…
Stephen Collings
  • 17,373
  • 17
  • 92
  • 180
5
votes
5 answers

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 me what the right answer is/ where I have gone…
Aks Mur
  • 51
  • 2
5
votes
3 answers

Contradiction:Maximum Power Transfer and High resistance of load

Whenever we load a circuit, there's a drop from the open circuit voltage \$v_{oc}\$ due to the internal source resistance or Thevenin's resistance\$R_{th}\$. So we need to have an \$R_{load}\$ that is very large compared to \$R_{th}\$, (i.e)…
Aravindh Vasu
  • 481
  • 4
  • 13
5
votes
3 answers

Thevenin Equivalent Voltage: why ignore the 3-kΩ resistor?

In order to find the Thevenin voltage here, why is it that the 3k Οhm resistor is ignored and no current goes through it? (hence \$V_{TH}=8mA \cdot 7kΩ = 56V\$)
fred
  • 451
  • 1
  • 5
  • 16
5
votes
4 answers

Thevenin equivalent of nmos

I was reading my textbook(razavi) and came across this circuit where to calculate vout2/vin1 he drew a thevenin equivalent of nmos. I dont understand how thevenin voltage(Vt) and Rt in the equivalent circuit is Vin1 and 1/gm1?? The procedure for…
user98208
1
2 3
…
37 38