Kirchhoff's Law circuit question

  • Thread starter Thread starter RyanTG
  • Start date Start date
  • Tags Tags
    Circuit Law
Click For Summary

Homework Help Overview

The discussion revolves around applying Kirchhoff's laws to analyze a circuit with resistors. The original poster seeks to determine the current flowing through each resistor but expresses confusion regarding the application of these laws and the methodology involved.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the original poster's attempts to apply Kirchhoff's laws, including the use of Maxwell's loop. Questions arise about the direction of current flow and the implications of potential differences across resistors.

Discussion Status

The conversation includes various interpretations of the circuit setup and the application of Kirchhoff's laws. Some participants offer guidance on marking potentials and understanding current flow, while others express frustration with the original poster's presentation of their work. There is no explicit consensus on the correct approach or answers.

Contextual Notes

Participants note issues related to the orientation of the circuit diagram and the clarity of the original poster's attempts. There is mention of varying results based on different approaches to the Maxwell loop, indicating potential confusion in the application of the laws.

RyanTG
Messages
13
Reaction score
0
I've attached the circuit layout.

Q) Find the current flowing through each of the resistors.

I've uploaded my attempt.


What am I doing wrong? I thoroughly do not understand kirchhoff laws. I follow the sign rules, I try to do the maxwell loop thing and I'm still getting wrong answers.

If I do the maxwell loop on the circuit, is there no need for a I0? If I don't do the maxwell loop then I never get the right answer for any of the questions.

I don't understand why I can't do this.

Thanks.
 

Attachments

  • figure1law.png
    figure1law.png
    4.6 KB · Views: 556
  • figure1answer.jpg
    figure1answer.jpg
    38.9 KB · Views: 563
Physics news on Phys.org
You're asking for help and you post the work SIDEWAYS? Doesn't work for me. No interest in getting a kink in my neck.
 
Maybe it could stem from the fact that you have current flowing both to the top of the page and to the bottom of the page, at the same time, through the middle section with the 4 ohm wire... Mark your potentials on the circuit to see which way the current's flowing.
 
What's the potential at the junction above the 4 ohm resistor? What does that tell you about the potential difference across the 1ohm resistor? What does that tell you about the current through the 1 ohm resistor remember V = IR.
 
I'm sorry man, it is saved vertically on my computer, I didn't purposefully upload it to be awkward.

There is no harm in just saving it to your computer and rotating it. I don't understand why I would be denied help because of something as petty as that.

Here you go, rotated.


Having a second go at it, I'm getting I1 as -4.5A, but a different value for I2 depending on which way I do my maxwell loop thing in the second half of the circuit...
 

Attachments

  • figure1answer.jpg
    figure1answer.jpg
    23.8 KB · Views: 543
Oh I think I get it now.

Is the correct answer: I1 = -5A, I2 = 5.5A?

Should the maxwell loop always go in the direction that the current would flow in that part of the circuit? So for the second half, it should go positive to negative, so my loop is the wrong way around?

And I've been plugging I1 back into the first simultaneous equation that governs the emf for the first loop, instead of plugging it into the second one, to find I2.
 
You know what I don't even know anymore...
 
figured it out finally i think... my answers were correct in that image, my method is wrong but just happened to be correct in that instance.
 
I got those numbers as well, but i think you have to add them together through the 4 ohm resistor, so .5 through the 1 ohm and 1.5A through the 1 ohm.
 

Similar threads

  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 16 ·
Replies
16
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
22
Views
4K
Replies
5
Views
6K
Replies
3
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 18 ·
Replies
18
Views
3K