What is the Thévenin equivalent of this circuit?

In summary, the problem located in the attachment is that the author is trying to use equations relating to simplifying circuits to get the total resistance, but the book they are using is telling them they are wrong.
  • #1
maximade
27
0

Homework Statement


Problem located in attachment.

Homework Equations


Parallel, series and wheatstone bridge equations for resistors

The Attempt at a Solution


Converted the circuit to look less confusing. Work shown in other attachment.
I am simply using the equations relating to simplifying circuits to get R total or th, but the book I am using is telling I am wrong. Thoughts?

Thanks.
 

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  • #2
hi maximade! :smile:

hmm … i get the same as you (1.5 Ω) :confused:

anyone else? :smile:

btw, it might be easier if you started with a different diagram …

put it all inside a triangle with edges 3 3 and ab, and you should see a symmetry that makes it a lot easier :wink:
 
  • #3
maximade said:
I am simply using the equations relating to simplifying circuits to get R total or th, but the book I am using is telling I am wrong.
It's a talking book? :-p

I'd say you're half right. A Thévenin equivalent involves a voltage source together with a series resistance. So, what's your voltage?
 
Last edited:
  • #4
Yes, it is a talking book haha. (Don't know how to do that quote thing you did)

Correct me if I am wrong but because the current source is the load, I thought I just turn it into an open circuit then solve for resistance from there.

I could just be not understand the whole process.

Thoughts?
 
  • #5
maximade said:
Yes, it is a talking book haha. (Don't know how to do that quote thing you did)
Use the "Quote" button on the post in question to start your reply with that post's text included as a quote.

Correct me if I am wrong but because the current source is the load, I thought I just turn it into an open circuit then solve for resistance from there.
Ah, but the current source is not the load; it's part of the circuit. It just happens to lie across the output nodes. If you think about the network of resistors "behind" it being reduced to a single resistor, then what would the current source and resistor look like (in terms of circuits you might be familiar with)?
 
  • #6
maximade said:
Correct me if I am wrong but because the current source is the load, I thought I just turn it into an open circuit then solve for resistance from there.
It may look like a bridge arrangement, but no one says it can't be used in an exercise where you just need a jumble of resistors. :smile:

The question asks that you find the Thévenin equivalent of the circuit as it appears at terminals (a,b). The source is, in this question, part of that circuit. At terminals (a,b) you will see a source feeding into a resistance. You have correctly determined the equivalent single resistance, now imagine that source connected across that resistance. How much current will be flowing? What voltage will be measured at the terminals (a,b)?

Describe what you have so that it fits the classic Thévenin circuit.
 

FAQ: What is the Thévenin equivalent of this circuit?

What is Thevenin Equivalent Circuit?

Thevenin Equivalent Circuit is a method used in electrical engineering to simplify complex circuits into a single voltage source and a single resistor. It allows for easier analysis and calculation of circuit behavior.

How is Thevenin Equivalent Circuit calculated?

Thevenin Equivalent Circuit is calculated by removing the load resistance from the circuit and finding the open-circuit voltage and the internal resistance. The open-circuit voltage is the voltage across the load resistance when it is removed, and the internal resistance is the resistance seen by the load when all the voltage sources are turned off.

What is the purpose of Thevenin Equivalent Circuit?

The purpose of Thevenin Equivalent Circuit is to simplify complex circuits into more manageable and easier to analyze circuits. It allows for easier calculation of current and voltage values, and also helps in predicting circuit behavior.

Can Thevenin Equivalent Circuit be used in all types of circuits?

No, Thevenin Equivalent Circuit can only be used in linear circuits with independent voltage and current sources. It cannot be used in circuits with dependent sources, non-linear elements, or varying components like capacitors and inductors.

What are the limitations of Thevenin Equivalent Circuit?

Thevenin Equivalent Circuit assumes that the circuit is in steady-state and that the load is resistive. It also does not take into account any frequency-dependent behavior of the circuit, making it less accurate for high-frequency circuits. Additionally, it may not provide accurate results for circuits with highly non-linear components.

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