Just one little question on the frequency band of the series RLC filter

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SUMMARY

The discussion centers on the frequency band rejection of a series RLC filter and its dependence on resistance (R). The user derived the formula for the bandwidth, Δω, as Δω = R/L, while their textbook states Δω = R/2L. The user seeks clarification on the discrepancy between their calculation and the textbook's definition of Δω, which is the frequency difference at half the maximum power on the power vs. generator frequency curve. This indicates a misunderstanding of the definitions used in the context of RLC circuits.

PREREQUISITES
  • Understanding of RLC circuit theory
  • Familiarity with the concept of Quality factor (Q)
  • Knowledge of angular frequency (ω) and its relationship to frequency (f)
  • Basic principles of power in electrical circuits
NEXT STEPS
  • Review the derivation of the Quality factor (Q) in RLC circuits
  • Study the definitions and implications of bandwidth in filter design
  • Learn about the power vs. frequency curve in RLC circuits
  • Examine the differences between theoretical and practical applications of RLC filters
USEFUL FOR

Electrical engineers, students studying circuit theory, and anyone involved in designing or analyzing RLC filters will benefit from this discussion.

Lisa...
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Hey! I really need to find out how the width of the frequency band rejected depends on the resistance R of the following circuit:

http://img418.imageshack.us/img418/8168/rlc2wf.gif

I've done the following:
Q= \frac{\omega_0}{\Delta \omega}

so

\Delta \omega = \frac{\omega_0}{Q}

with

Q= \frac{\omega_0 L}{R}

Substitution gives:

\Delta \omega = \frac{\omega_0}{\frac{\omega_0 L}{R}}

=\frac{R}{L}


\Delta f= \frac{\Delta \omega}{2 \pi}

= \frac{\frac{R}{L}}{2 \pi}

= \frac{R}{2 \pi L}


Though my textbook says that

\Delta \omega = \frac{R}{2L}

... and it defines the delta omega as the frequency difference between the two points on the average power vs generator frequency curve where the power is half its maximum value...

So am I wrong or is the textbook's answer just confusing?
 
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