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Amcote
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Homework Statement
For the RC circuit shown in Fig. 1, at some frequency the peak voltage across the capacitor and resistor are equal. Find the frequency at which this occurs. Show that the peak voltage across the capacitor or the resistor at this frequency is given by Vin/ √ 2. How would this compare if we had two resistors R instead of a resistor and a capacitor?
fig 1. is an RC circuit with 1 capacitor (0.1μF), 1 resistor (1kΩ) and a voltage source.
Homework Equations
1. Zc = −i/ ωC
2. |Zc| = |Vc|/ |I| = 1/ ωC ,
3. R = V/I
4. ω=2πf
The Attempt at a Solution
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To be honest it's been a very long time since I've done any physics and I'm having a little difficulty re-learning all the circuit stuff.
To get the frequency the only thing I can think of is setting Vc equal to V to get
IR=I/wC=I/2πfC
Then,
f=1/2πCR
so,
f=1/2π(0.1μF)(1kΩ)=1591.55Hz
As for the next part, I'm really not sure what it is asking. Perhaps if I knew exactly what Vin/ √ 2 is then I'd be able to make some progress.
But using the formulas, the peak voltage across the capacitor is
|Vc|/ |I| = 1/ ωC (I think)
And I don't know a formula for the peak voltage across the resistor, the only formula I have for the resistor is
R = V/IAnd actually another thing I am confused about is the difference between resistance and impedance because it seems they use these terms interchangeably. Thanks guys.