What is the solution to the non-linear device problem?

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The discussion centers on solving a non-linear device problem using Kirchhoff's voltage law (KVL). The user initially struggles with the equation involving voltage and current ratios, specifically \(\frac{1+v_Q/i_Q}{2+v_Q/i_Q} = 10\). They clarify that the 1-ohm resistor is in parallel with a 10V source, leading to a voltage drop calculation that includes the current through another resistor. After reevaluating their approach, they recognize the error in equating resistance to voltage and arrive at a solution of \(V_{q} = 2V\). The conversation emphasizes the importance of correctly applying KVL and understanding the relationships between voltage and resistance in circuit analysis.
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Homework Statement


See figure


Homework Equations





The Attempt at a Solution



Again, see figure I tried something and it looked promising but the answer doesn't work out.

Any ideas?
 

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Could you explain your reasoning to get the equation

\frac{1+v_Q/i_Q}{2+v_Q/i_Q} = 10

I don't see how you're applying Kirchoff's voltage law to get that.
 
You know the 1 ohm resistor is in parallel with the 10V source, therefore the voltage across it is 10V. Now we can subtract from the 10V the drop across the other 1 ohm resistor which is 1*Iq, and subtract Vq. 10 - 1*Iq - Vq=0, we can plug in for Iq which is Vq^2+2*Vq. Solve for Vq, you'll obtain a positive and negative value but only the positive makes sense because of our polarity.
 

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When you combine the circuit resistances, first by adding the two in series, and then by calculating the two in parallel, you get a value of resistance (keep in mind SI units).

In your equations you say this resistance is equal to 10 volts by KVL.

\frac{1+v_Q/i_Q}{2+v_Q/i_Q} = 10

Resistance does not equal voltage.
 
Thanks for the responses. I must have been out of it at the time putting resistance equal to voltage lol.

I understand now.

V_{q} = 2V
 

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