Question

Can the voltage drop across the inductor or the capacitor in a series LCR circuit be greater than the applied voltage of the ac source?Justify your answer

Answer 1

The answer is Yes.

Yes, the voltage drop across the inductor or the capacitor in a series LCR circuit can be greater than the applied voltage of the AC source.

This is because the voltage drops across these two elements are not phase voltages. Hence, the summation of their voltage cannot be done algebraically. The vector summation concept is followed in this case.

Answer 2

Yes, it can be. In fact, this method was also a popular method for voltage boosting.

In LC resonance, the impedance offered by the L and C are same have same absolute value but different signs. Thus when you add the all the impedances in the circuit only resistive impedance is seen by the source. If your resistive impedance is sufficiently small, the current drawn will be quite large.

Now, if the inductive impedance is quite large, the voltage across it will also be very large. By proper design, you can make several times higher than the supply voltage.