Solve Vx in Nodal Voltage Analysis

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Gclip5
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Homework Statement


Find Vx.
http://imageshack.com/a/img853/3093/ssdr.png

Homework Equations


NONE


The Attempt at a Solution


I just need one more equation so far I have:
1. V1 = 4v
2. V3 = 2Vx
3. (V1-V2)/2 = V2-V3+V2
 
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Gclip5 said:

3. (V1-V2)/2 = V2-V3+V2

You made a error

(V1 - V2)/2Ω = V2/1Ω + ??
 
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I don't see the error. The voltage is dropping across the resistor from V2 to V3. Likewise for the other one ohm resistor from V2 to ground.
 
Gclip5 said:

3. (V1-V2)/2 = V2-V3+V2

How can this be true if the left side of a the equation has a unit of Amps.
(V - V)/Ω = V/Ω = A
But on the right side you only have a voltage.
And as we all know Ampere are not equal to Volts
 
Jony130 said:
How can this be true if the left side of a the equation has a unit of Amps.
(V - V)/Ω = V/Ω = A
But on the right side you only have a voltage.
And as we all know Ampere are not equal to Volts

Well I guess the equation he meant to write is:

(V1-V2)/2 = (V2-V3)/1 + (V2-0)/1 which is equal to (V1-V2)/2 = V2-V3 + V2
 
Yeah sorry about the poor labeling, but Nugso is correct. I still can't figure out a third equation to get.
 
Ok I see the problem.
So all you need is this

(V1-V2)/2 = (V2-V3)/1 + (V2-0)/1 (1)

2Vx = V3 = 2(V1 - V2) (2)

And you solve for V2.
 
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THANKS. Can't believe i didnt see that.