Q Factor in Series-Parallel Shunt Circuits

[phantomvommand]

The above content discusses the conversion of RL (in series) to RL (in parallel). Importantly, the context is that the RL (in series) was in parallel with a capacitor.

I am interested to know the following:

Q1. Why is $\frac {\omega L} {R} = Q$ true for this circuit, given that this formula was derived for the pure series RLC circuit (and is not applicable to this RL||C circuit unless we are assuming R-L-C is approximately equal to R-L||C)?

Q2. Notably, the conversion between RL to R||L is not technically true, since it takes $R_L >> R$ and therefore ignores R. Is there a physical interpretation for the technical impossibility of converting from RL to R||L? Related to this, what is the physical meaning of a circuit in a situation where $R_L$ is not much larger than R, and therefore cannot be converted from series to parallel?