Capacity with 2 R in RC circuit

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Homework Help Overview

The discussion revolves around an RC circuit involving two transistors, focusing on the equivalent circuit in the dynamic range and low frequency. The original poster seeks to determine the capacitance given a frequency, with a specific relationship involving resistance and frequency.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the relationship between frequency and resistance in the context of the circuit, with some questioning how to treat the resistors in relation to the capacitor. There is also an attempt to clarify the gain of the circuit and its implications for the frequency equation.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the circuit configuration and the role of the resistors. Some guidance has been offered regarding the gain and its relationship to the frequency, but no consensus has been reached on the treatment of the resistors in the circuit.

Contextual Notes

There is uncertainty regarding whether the resistor before the capacitor should be considered part of the input voltage or ignored, which is a point of contention among participants. Additionally, a request for a circuit diagram indicates that visual representation may be necessary for clarity.

potatowhisperer
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Homework Statement


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 .[/B]

Homework Equations


omega =1/rc

The Attempt at a Solution


Is this true . Omega = 1/ (R1 + R2 )c
 
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i apologize ; apparently we calculate the gain : Av = Vo / Vi , and we deduce the form of omega from there , thank you very much .
 
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.
 
Can you provide a circuit diagram to make the configuration more clear? Show where Vo and Vi are measured.
 

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