Calculating Voltage in a Simple Divider Circuit

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Discussion Overview

The discussion revolves around calculating the voltage at a node between two resistors in a voltage divider circuit, specifically focusing on a schematic involving two voltage sources and resistors. The context is primarily related to a homework-like scenario, although the original poster (OP) indicates it is part of their study rather than a formal homework question.

Discussion Character

  • Homework-related
  • Technical explanation

Main Points Raised

  • The OP attempts to apply Kirchhoff's Voltage Law (KVL) to calculate the current and voltage at the node, but expresses difficulty in determining the current due to a potential error in their equation.
  • Another participant questions the notation used in the schematic, particularly the representation of the voltage sources and their polarities, suggesting that the right-hand voltage source is confusingly labeled as -15V while the left is +15V.
  • There is a mention of the voltage across the string of resistors, indicating a need for clarification on how the voltage is distributed in the circuit.

Areas of Agreement / Disagreement

The discussion remains unresolved, with participants expressing confusion over the schematic and the calculations involved. There is no consensus on the correct interpretation of the voltage sources or the resulting calculations.

Contextual Notes

The discussion highlights potential ambiguities in the schematic notation and the assumptions made regarding voltage polarities. The OP's initial equation appears to be based on an incorrect understanding of the circuit, leading to difficulties in calculating the desired voltage.

fonz
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Homework Statement



Not technically a homework question but part of a piece of work I am studying. I need to calculate the voltage at the node in between the 10k and 27k resistors in the following schematic. I'll call it Vo.

https://www.physicsforums.com/attachments/213624

Homework Equations



KVL

The Attempt at a Solution


[/B]
By KVL:

15 - i(10k) - i(27k) -15 = 0

i(-37k) = 0

So I can't work out the current and therefore can't work out the voltage.
 
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Still to be posted in homework. Never mind. What about the signs (all four of them...) ?
 
The notation is a bit confusing, but whatever. The right-hand voltage source is shown with the + end toward the resistors, but the value of the supply is shown as -15V. So the left end of the resistors is sitting at +15V and the right end is at -15V. So what is the voltage across the string of resistors?
 
Thread closed for Moderation...
 
OP deleted his question after receiving help on homework. That is not allowed. Poster is on a short vacation from the PF.

The image in his (now restored) OP was two voltage sources, +15V at the left and -15V at the right, and two resistors in the middle as a divider. Thread is closed and archived.
 

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