The impedance of an RC series circuit is calculated in the next formula:
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Formula 1
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Where:
Z is the impedance in ohm (Ω)
Xc is the capacitive reactance in ohm (Ω)
Rc is the resistance in ohm (Ω)
Derivated Formulas:
Formula 2
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Formula 3
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Application Example:
Determinate the impedance of a 0,1 µF capacitor in series with a 10 ohm resistor in a circuit where the capacitive reactance of the capacitor is 309 Ω.
Data:
Xc = 30 Ω
R = 10 Ω
Applying formula 1
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