What is the characteristic of the current flow in a series R-L-C circuit at resonance?

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Multiple Choice

What is the characteristic of the current flow in a series R-L-C circuit at resonance?

In a series R-L-C circuit, resonance occurs when the inductive reactance equals the capacitive reactance, so they cancel and the circuit behaves like a purely resistive path. That makes the impedance as small as possible for the given circuit, equal to the resistance R. Since current is I = V / Z, with the source voltage V fixed, the current reaches its maximum at resonance because Z is at its minimum (the resistance). Note that in an ideal circuit with zero resistance, the current would be infinite, but real circuits have some resistance, so the current is large but finite. The other options don’t fit because resonance does not produce zero current, nor does it imply minimum current or direct current; resonance is an AC concept at a specific frequency where the reactive effects cancel.

In a series R-L-C circuit, resonance occurs when the inductive reactance equals the capacitive reactance, so they cancel and the circuit behaves like a purely resistive path. That makes the impedance as small as possible for the given circuit, equal to the resistance R. Since current is I = V / Z, with the source voltage V fixed, the current reaches its maximum at resonance because Z is at its minimum (the resistance).

Note that in an ideal circuit with zero resistance, the current would be infinite, but real circuits have some resistance, so the current is large but finite. The other options don’t fit because resonance does not produce zero current, nor does it imply minimum current or direct current; resonance is an AC concept at a specific frequency where the reactive effects cancel.

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