In an ac LRC circuit, if XL > XC, the circuit is said to be predominantly “inductive.” And if XC > XL, the circuit is Said to be predominantly “capacitive.” Discuss the reasons for these terms. In particular, do they say anything about the relative values of L and C at a given frequency?
XL = XC at the resonant frequency. If the circuit is predominantly inductive, such that XL > XC, then the frequency is greater than the resonant frequency and the voltage leads the current. If the circuit is predominantly capacitive, such that XC > XL, then the frequency is lower than the resonant frequency and the current leads the voltage. Values of L and C cannot be meaningfully compared, since they are in different units. Describing the circuit as “inductive” or “capacitive” relates to the values of XL and XC, which are both in ohms and which both depend on frequency.
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