Engineering Board Exam Reviewer · Circuit Theorems in AC Analysis · easy
The complex impedance of an ideal capacitor with capacitive reactance XC is
- +jXC
- XC
- -jXC
- jXC2
Answer
C. -jXC
Solution
The capacitor's voltage lags its current by 90°, so its impedance is the negative imaginary quantity ZC=1/j C=-jXC.
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