Find the frequency in an LRC circuit

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SUMMARY

The discussion centers on finding the frequency in an LRC circuit, specifically addressing the condition where the damping factor (alpha) exceeds the natural frequency (w0). When this occurs, the equation w = w0^2 - alpha^2 results in a negative value, indicating that the circuit will not oscillate. To resolve this, one must recognize that not all RLC circuits oscillate under these conditions, and alternative methods must be employed to analyze the circuit's behavior.

PREREQUISITES
  • Understanding of RLC circuit components: Resistor (R), Inductor (L), and Capacitor (C)
  • Familiarity with the concepts of natural frequency (w0) and damping factor (alpha)
  • Basic knowledge of complex numbers for handling negative values in frequency calculations
  • Proficiency in circuit analysis techniques, including differential equations
NEXT STEPS
  • Study the conditions for oscillation in RLC circuits and the implications of alpha > w0
  • Learn about the use of complex impedance in analyzing non-oscillating circuits
  • Explore the concept of underdamped, critically damped, and overdamped responses in RLC circuits
  • Investigate alternative methods for frequency analysis in circuits that do not oscillate
USEFUL FOR

Electrical engineers, physics students, and circuit designers who need to understand the behavior of RLC circuits, particularly in non-oscillating scenarios.

tony873004
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w=w0^2 - alpha^2
and then take the square root of this.

But I keep getting a negative number and I can't put this under the root symbol. I remeber he discussed this in class but I can't find it in my notes. How do I deal with the negative so I can find the frequency?
 
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Not all RLC circuits will oscillate. If R, L, & C are such that
alpha > w0
you get the situation you are describing.
 

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