Quality Factor in RLC circuit

Hello
according a text quality factor is the ratio of energy stored to energy lost in a component.
but in rlc or lc and rl the Q=wL/R (w=omega)
why we didn't use the capacitor reactance instead of reactance of Self?

The resistance comes from the coil. And the greater the resistance in the loop, the greater the damping effect, and the lower the quality factor.

Since the capacitor is omitted in the equation, then it must be because it is regarded as having a pure action.

Most of the time capacitors are much higher Q then a coil in a resonate tank but not really relevant.

Use X_inductor or X_cap as they are same at resonance.

Q is also equal to F_resonance / BW3db. (for a single LC tank)

Distinguish the different cases: RLC, RL or RC circuit.

For a resonant (RLC) circuit: Q = 2*pi*(max energy stored in L or C)/(energy dissipated in 1 cycle).

At resonance, the reactance of the inductor and that of the capacitor have the same value: w₀L=1/(w₀c)

The formula Q=w₀L/R=1/(w₀CR) hold for a series RLC circuit.
For a parallel circuit: Q=R/(w₀L)=w₀CR.

Regards

Z