Engineering Board Exam Reviewer · RLC Circuits and Resonance · easy
At the resonant frequency of a series RLC circuit, the impedance is
- maximum and equal to R
- zero
- equal to XL+XC
- minimum and equal to R
Answer
D. minimum and equal to R
Solution
At resonance XL=XC and the two reactances cancel, leaving only R. The impedance is at its minimum value, |Z|=R, and the current is at its maximum.
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