What behavior does the line current exhibit at parallel resonance_______________?
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Answer: A. Minimum
Explanation
At parallel resonance, the total impedance of the tank circuit reaches its absolute maximum possible value. Ohm's law dictates that a maximum circuit impedance must result in a minimum line current drawn. The external source supplies only the energy needed to overcome internal resistive losses within the network. Parallel resonant circuits are commonly known as tank circuits in radio frequency oscillator applications. Circulating currents inside the parallel branches remain very high even though the external supply current drops. Quality factor determines the sharpness of the impedance peak and the magnitude of the minimum line current.
Maximum describes the behavior of circuit impedance or circulating current rather than the external line current. Quite large is an imprecise qualitative description rather than the exact minimum electrical characteristic observed. None of the above is incorrect because minimum accurately describes the line current at parallel resonance.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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