How can I derive the quality factor in an RLC circuit?

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SUMMARY

The quality factor (Q) in a series RLC circuit is derived using the formula Q = ωL/R, where ω represents the angular frequency. The derivation begins with the definition of Q as Q = 2π * (energy stored in the resonator) / (energy lost per cycle). The peak stored energy is calculated as LI² / 2, while the power dissipated in resistance is I²R/2. The time period of one cycle is expressed as 2π/ω, leading to the final expression for Q. For parallel circuits, the quality factor is the reciprocal of the series expression.

PREREQUISITES
  • Understanding of RLC circuit components (Resistor, Inductor, Capacitor)
  • Familiarity with angular frequency (ω) and its relation to frequency (f)
  • Knowledge of energy storage in inductors and resistive power dissipation
  • Basic algebra for manipulating equations and formulas
NEXT STEPS
  • Study the derivation of quality factor in parallel RLC circuits
  • Explore the implications of quality factor on circuit performance and resonance
  • Learn about energy storage in capacitors and its effect on Q
  • Investigate the role of damping in RLC circuits and its impact on quality factor
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Electrical engineers, physics students, and anyone involved in circuit design and analysis, particularly those focusing on resonance and quality factor in RLC circuits.

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I need some help deriving the quality factor in an rcl circuit
Q=Lw(sub 0)/R. So far I know that Q=w(sub 0)/delta but my professor used this formula to continue the derivation delta w=R/L and I don't know where it comes from. Can anyone give me a hint?
 
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Quality factor is defined by
Q= 2*pi*(energy stored in resonator)/(energy lost per cycle).

The peak stored energy is LI^2 / 2.

The power dissipated in the resistance is I^2R/2, in terms of the peak current.
The time in one cycle is 1/f or, in terms of angular frequency, 2\pi/\omega. Putting these into the definition of quality factor gives
Q=\frac{\omega L}{R}.

EDIT: clean up equation rendering and add following:
Note that this is true for a series LCR circuit. For a parallel circuit Q is one over the expression on the right!
 
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thanks a lot
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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