Resonant frequency
Resonance in RLC series circuit
The current I in an RLC series circuit is given by
Some equation
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Current is obtained in the circuit when the impedance z in the above equation is minimum. This happens when
Some equation
Resonance
Resonance is said to occur in an alternating current series circuit when the maximum current is obtained from such a circuit.
Resonant frequency
This is the frequency at which resonance occurs in a given AC series circuit. It is denoted by f0. The resonant frequency is the frequency at which the capacitive and inductive reactance in the circuit are equal
Some equation
The variation of current, I and frequency f, in an RLC series circuit is shown in the figure..
Image
From the diagram we see that at frequency above or below the resonant frequency the current is less than the maximum current Imax. At f = f0, the current is maximum.