# Electrical Resonance

1. Apr 10, 2009

### jayjay112

Explain the meaning of the term resonance as applied to a series A.C circut.

What is the best way of answering this question. Im kind of confused on what to include in the definition and what not to include.

We know that the capacitive reactance and the inductive reactance depend on frequency. The value of frequency when w = 1/(sqaureroot of LC) = 2.pi.f0

The frequency f0 is called the resonance frequency of the circuit. At this frequency the impedance is smallest. At this frequency the circuit is said to be at resonance. At resonance the current is in phase with the generator voltage.

Is this an ok answer or is their a better one i could use???? Also can anyone find a link to the phasor diagram to illustrate this??

Thank you.

2. Apr 10, 2009

### jayjay112

Or is this a better definition....

Resonance in AC circuits implies a special frequency determined by the values of the resistance , capacitance , and inductance . For series resonance the condition of resonance is straightforward and it is characterized by minimum impedance and zero phase.

3. Apr 10, 2009

### jayjay112

can anyone find a link to the phasor diagram to illustrate this??

4. Apr 10, 2009

### Staff: Mentor

I think that's a better one. And I'm not sure that a phasor diagram will be of much help.

BTW, the resistance isn't a factor in the resonance per se. It's a damping factor that causes a resonance to diminish over time, if it is not being actively driven.

You might google "tank circuit" for more ideas on resonance. Also look into how the energy in an LC resonant circuit oscillates back and forth between _____ and _____ ...