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**[SOLVED] Wien Bridge Frequency Proof**

**1. Homework Statement**

The ac bridge circuit shown is called a Wien bridge (also Wein bridge).

Show that when the bridge is balanced, frequency is found by the Eqn attached.

**2. Homework Equations**

w=2*pi*f

Using the number from each branch as a guide, the general solution to AC bridges is Z4 = (Z3/Z1)*Z2

**3. The Attempt at a Solution**

I keep trying to solve for impedences to plug into the second equation provided, but my j values do not cancel and the equation left is rather messy (R2R4C2C4*w^2 +jw(RzR4C2 -R2C2 -R4C4) +1 = 0.

For my impedence values I have been using

Z1 = R1

Z2 = R2 -j/wC2

Z3 = R3

Z4 = (R4/jwC4)/(R4 +jwC4)

Any help with this would be greatly appreciated.