Reworking the formula for the current resulting from an ac emf applied to an RLC series circuit leads to the universal resonance formula.
Resonance occurs in a circuit when the maximum value of the current is achieved. Examining the numerous formulas associated with the RLC series circuit, we find that the following conditions are synonymous with resonance:
Note that at resonance, VL = VC, so that the net voltage across the reactive elements is zero (added as phasors). However, each reactive element itself may have a very large voltage. In a high-Q circuit, the voltage across the reactive elements may be many times larger than the applied emf.
Last updated Dec. 17, 1997.
Copyright George Watson, Univ. of Delaware, 1997.