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# Op Amp Practice with Voltage Division

Practice question for ECE201: "Linear circuit analysis I"

By: Chinar Dhamija

Topic: Op Amp

## Question

Find the value of Vout.

The first step would be to solve for i using Ohm's Law.
$i = \frac{12}{4}$
$i = 3A$

We know that $V_+ = V_-$.
In order to find $V_+$ we need to use voltage division at the node connecting the 2 and 4 ohm resistor.
$V_+ = \frac{4}{4 + 2} * 9$
$V_+ = 6 = V_-$

Now that we know the voltage at the $V_-$ node we can find Vout by using the following equation.
\begin{align} i = \frac{V_- - Vout}{8}\\ 3 = \frac{6 - Vout}{8}\\ 24 = 6 - Vout\\ Vout = -18 V\\ \end{align}

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