Amateur ExtraE5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

A
Answer
Electrical principles and calculations
Type
A
Minimum
B
Maximum
C
R/L
D
L/R

Answer Notes

At resonance, the inductive and capacitive branches of a parallel RLC circuit draw reactive currents that are 180 degrees out of phase. Because these currents completely cancel each other out from the perspective of the power source, the net reactive current drawn from the input is zero. As a result, the total impedance of the parallel circuit reaches its maximum possible value, equaling just the parallel resistance. According to Ohm's law (I = E/Z), when impedance is at its maximum, the current drawn from the source is at its minimum. Distractors suggesting maximum current describe the behavior of a series RLC circuit, where reactive impedances cancel to zero and current spikes to a maximum.
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What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?
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What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?