# Homework Help: Calculate amplitude and phase of a filter cricuit

1. Apr 28, 2015

### Guinness666

• homework type question so moved to the homework forum

I have the values for all the voltages and currents. I'm wondering how I go about it, given that v3 = v30 (cos (Θ3) + isin(Θ3)) and I have a value for v3. Since v3 = i4 * Z where Z is C3 and R2 in parallel, there'd still be 2 unknowns. I feel as though I'm missing something obvious, if anyone could give me a little help, that'd be great.

2. Apr 28, 2015

### Staff: Mentor

You're wanting to calculate v3 in terms of v0? You'll need to use mesh or nodal analysis.

3. Apr 28, 2015

### Guinness666

I already know the values of i1, i2, i3, i4, v1, v2, v3 from doing a nodal analysis on a circuit earlier in this question which is exactly the same apart from that it contains resistors instead of capacitors and inductors.

4. Apr 28, 2015

### Staff: Mentor

So you'll retrace the steps in the analysis, but substituting
some R's with $j\omega L$ or $\frac 1{jwc}$.

5. Apr 30, 2015

### Guinness666

This is the earlier part,