How Do You Find Frequency in an RC Circuit?

AI Thread Summary
To find the frequency in an RC circuit, the impedance (Z) is calculated using the formula Z = [R^2 + (1/wC)^2]^(1/2), where w is the angular frequency. The confusion arose from differing resistance values provided in the problem, leading to uncertainty about the setup. Initially, there was an assumption that Z equals R, which resulted in an incorrect equation. Ultimately, the correct frequency equation f = 1/(2πRC) was confirmed by using the appropriate values from the problem. The user resolved their confusion and sought assistance on deleting the thread after finding the solution.
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RC Circuit, Finding Frequency? [Solved]

Solved =]

Homework Statement



question.jpg


Homework Equations



Z = [ R2 + (1/wC)2 ]1/2
where Z is impedance, w = (omega) = angular frequency

Xc = 1/(wC)

w = 2(pi)f

(tau) = RC
where (tau) is the time constant

The Attempt at a Solution


I'm more confused than anything. Like I'm not sure what the set up is.
setup.jpg


Just looking at the problem itself, the first part seems to give different numbers. When in the first part R = 4857.1 Ohms, and then in the second part R = 3629.6 Ohms?

At first I was working under the assumption that Z = R, but that would result in 0=1/(wC)
Then I googled impedance of the capacitor and some sources say that that is Xc, the capacitive reactance. So I solved R = Xc = 1/(wC) got that f = 1/ [ RC2(pi) ] , but when I tried plugging it in, I still couldn't get the answer that they have.EDIT:
Nevermind. I just figured it out. Turns out I was right for the frequency equation. I just used the numbers given instead in the second part and completely ignored the first part, and got the answer.

Um, how do I delete a thread?
 
Last edited:
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