High school circuit diagram question

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Homework Help Overview

The discussion revolves around a circuit diagram question involving resistors and voltage dividers. The original poster expresses uncertainty about their calculated equivalent resistance of 3 Ohms, noting that it is not listed as an option, which raises doubts about their answer.

Discussion Character

  • Exploratory, Conceptual clarification, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the concept of voltage dividers and question the relationship between current and voltage in the circuit. The original poster reflects on their understanding of why the bottom resistances might be lower than the top and seeks alternative methods to approach the problem.

Discussion Status

The conversation is ongoing, with some participants providing guidance on the voltage divider concept. The original poster appears to have a breakthrough in understanding, indicating a productive direction in the discussion.

Contextual Notes

There is a mention of the original poster's confusion regarding the relationship between resistances and current flow, as well as a request for adherence to the forum's Homework Help Template.

rayclan
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Hi all. I got 3 Ohms in this question (top current = bottom current hence equivalent series resistance of top 2 and bottom 2 resistors must also be equal), but is that really the right answer? There is no option for 3 Ohms so I am beginning to doubt myself.
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Please use the Homework Help Template the next time you start a schoolwork question thread here. Thank you.

Your answer appears incorrect to me. Can you show the work you did to arrive at it? :smile:
 
berkeman said:
Please use the Homework Help Template the next time you start a schoolwork question thread here. Thank you.

Your answer appears incorrect to me. Can you show the work you did to arrive at it? :smile:

here is my answer: http://imgur.com/a/LJo5Y
 

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rayclan said:
here is my answer: http://imgur.com/a/LJo5Y
What can you tell us about voltage dividers? It's not about equal currents in the two branches, it's about equal voltage dividers... :smile:
 
berkeman said:
What can you tell us about voltage dividers? It's not about equal currents in the two branches, it's about equal voltage dividers... :smile:

ok when i equate the Vout of the top and bottom, i get 1.5V. that is the correct answer but it doesn't make sense in my head. why should the bottom resistances be lower than the top? using the water pressure analogy, wouldn't more electrons want to flow from the 2 ohms to the 3 ohms than R ohms to 4 ohms because they encounter less resistance there than the 4 ohms?

edit: what i am also trying to say is, is there another way to do this aside from using the concept of voltage dividers?

edit: hangon i get it now. thanks very much. I've never seen voltage dividers ever in my life before but it is intuitive.
 
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rayclan said:
edit: hangon i get it now.
Sweet, that's what we're here for. Welcome to the PF. :smile:
 

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