Saskatchewan Polytech Introductory Electrical Theory and Practices Exam Practice

In a series RLC circuit, resonance happens when the inductor’s reactance and the capacitor’s reactance cancel each other out, so the total impedance becomes purely real and equal to the resistance, Z = R. Because the reactive part drops to zero, the current for a given applied voltage is I = V/R, which is as large as the circuit allows for that R value. In an ideal case this impedance is exactly R; in real circuits small parasitics make it very close to R, hence “approximately equal to the resistor value.” The other statements don’t fit: the impedance is not maximum at resonance (the reactive cancellation makes it minimum, equal to R), it is not zero unless R is zero, and the current is not minimized—it's maximized for the given voltage.