RLC series resonant circuit, when the circuit is coupled with sinusoidal AC voltage, the sinusoidal AC current is generated in the circuit, and the current generates AC voltage on the resistance, inductor and capacitor respectively. Among them, the voltage on the resistor is the same as the current phase, the voltage on the inductor is 90° ahead of the current phase, and the voltage on the capacitor is 90° behind the current phase. This indicates that the voltage on the inductor is in the opposite phase to the voltage on the capacitor.
When the series resonant circuit resonates, the voltage on the inductor and the voltage on the capacitor are opposite in phase, equal in magnitude, and cancel each other. At this time, the resonant voltage is equal to the product of the current and the resonant impedance, because the resonant impedance is a pure resistance, so the resonant voltage is the voltage on the resistor, not the voltage on the capacitor.
Because the voltage of the inductor is induced during resonance, the capacitor is the voltage generated by charging and discharging during resonance. Their electrical Angle is one ahead and one behind. Of course the voltage will be different