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## Homework Statement

Given the ideal op-amp, determine the resistor R

_{2}and the current I

_{2}where V

_{in}=500mV, V

_{out}= 2.5 V, and R

_{1}=5kV.

## Homework Equations

No current passes through op-amps, the op-amp tries to make V+ and V- equal.

Ohm's law, voltage divider equation

## The Attempt at a Solution

Since V+ is 500mV, I assumed that the node between R

_{1}and R

_{2}must also be 500mV, as it is connected to V-. So 500mV = 2.5V(R

_{2}/(5000Ω+R

_{2})). I got R

_{2}to be 1,250Ω.

Then I found I

_{2}=V

_{out}/R

_{eq}= 2.5V/(1250Ω + 5000Ω) = .4mA.

However, I am unsure because I am not sure if I did the part with the op-amp right; namely, the node between the resistors being set to 500mV.