Electrical Resonance: Q-Factor, Active Resistance & Graphs

AI Thread Summary
The discussion revolves around calculating the active resistance in an electrical resonance circuit, where the Q-factor is used in the formula R=Q/sqrt(C/L). The calculated active resistance is approximately 8900 ohms, which raises a question about why this value is significantly lower than the 98000 ohms of the active resistor. Participants are seeking clarification on the discrepancy between the calculated resistance and the actual active resistor value. Understanding the relationship between Q-factor, active resistance, and resonance frequency is crucial for explaining this difference. The conversation emphasizes the need for a deeper insight into these electrical concepts.
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Homework Statement


The scheme is here: http://img196.imageshack.us/img196/9366/lcre.jpg
G generates soundwaves, Re are all 10 ohm resistors , R is an 98000 active resistor, L=100mH, C=0.253 μF
The assignment was to measure the voltage through different parts of the circuit near resonance frequency and draw some graphs, but that's not the issue here.
When calculating the active resistance from the formula
R=Q/sqrt(C/L),
where Q is the Q-factor, the result is ~8900 ohms. This answer is correct and supposed to be so, but I have to explain WHY is this 11 times less than in the active resistor and this is the problem here. Can anyone give me some good advice?
 
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