I have a derivation from a book that says(adsbygoogle = window.adsbygoogle || []).push({});

Q = 2π Es / Ed

Where Es is the energy stored in the resonant components. Dividing both by the period at resonance gives...

Q = ωo Es / Pd

This is where I'm stuck. The book says Es = 1/2 LI^2 at the instant that all of the energy is being stored in the inductor. Then it goes on to say the power dissipated in the series resistance, Pd is equal to 1/2 I^2 R. Why is it the average power?

Of course these both simplify down to ωoL/R.

And, how do you go from 1/2 LI^2 as the energy of the inductor to ωLI^2 as the power? The power is 4πf times the energy?

I think I posted this in the wrong section, sorry.

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# Trouble deriving series Q

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