# Capacity with 2 R in RC circuit

1. Dec 29, 2015

### potatowhisperer

1. The problem statement, all variables and given/known data
Initially we had a circuit with 2 transistor , we draw the equivalent circuit in the dynamic range and low frequency .
After that we simplified the Circuit by calculatuig Rin after the capacity .
So what we have left is a voltage source (ac) followed by a resistor followed by a capa followed by another resistor . The question is find c given f , we know 1/rc = 2pi f , the problem here is what is r .

2. Relevant equations
omega =1/rc

3. The attempt at a solution
Is this true . Omega = 1/ (R1 + R2 )c

2. Dec 29, 2015

### potatowhisperer

i apologize ; apparently we calculate the gain : Av = Vo / Vi , and we deduce the form of omega from there , thank you very much .

3. Dec 29, 2015

### potatowhisperer

okey turns out i am too dumb , for this , i thought i understood but it wasn t the case .
i just can not figure out if we should ignore the resistor before the capacitor , and think of it as part of Vin or not . please help.

4. Dec 29, 2015

### Staff: Mentor

Can you provide a circuit diagram to make the configuration more clear? Show where Vo and Vi are measured.