Finding a voltage across 2 nodes [Check answer - work already done]

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SUMMARY

The discussion centers on calculating the voltage across two nodes in a circuit using Kirchhoff's Voltage Law (KVL). The user initially calculated V1 as 18V and later revised it to 37.33V, with Vx determined as 13.33V. The calculations were verified against the schematic, revealing inconsistencies when considering multiple loops in the circuit. The conversation highlights the importance of clarifying circuit assumptions and the potential for misinterpretation in circuit analysis problems.

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naivy
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Homework Statement



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Homework Equations





The Attempt at a Solution


I got V1=18V
Here's my work:
AdrND.jpg
 
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Can you repost the original question and then rewrite your solution with some brief explanations to show what you are doing? i.e KVL (Right): V1 - Vx - 24 = 0
 
I got V1 = 37.33V, Vx= 13.33V. It checks when you plug the numbers into your schematic.

If V1 = 18V then Vx = 18 - 24 = -6V so i thru the 25K = -6/25 = 0.24 mA
whereas i thru the 5K would then be
(-3*6 - 18)/5 = -7.2 mA so that can't be right.
 
Vab = Va - Vb. Assuming Va is at V1+ and Vb is at V1-, what is V1?

Given V1, and using KVL around the right hand loop, what is Vx?
 
There are 2 loops? If so, V1 = 0!
 
Given the line drawn between V1+ and V1-, and the node 'dots', it seems a safe assumption that there are two loops, rather than just one with an errant line.

I got V1 = 37.33V, Vx= 13.33V. It checks when you plug the numbers into your schematic.

I did it your way as well though and got the same numbers, but wanted the original question reposted just to verify.
 
Two loops were my firat assumption too, but then I realized that that would make the problem pathological (viz. V1 = 0). Also, the OP calculated a finite (albeit erroneous) V1. So I decided that extra line must indicate voltage rise gnd to V1, although I did wonder why there was no arrow at the top of that line. Also, if two loops, why did the OP have - and + signs next to that line?
 
Also, if two loops, why did the OP have - and + signs next to that line?

It could possibly have been designed as a (trick) knowledge problem, rather than a circuit analysis problem. Needs more OP confirmation I suppose.
 

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