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RLC Resonant Frequency & Quality Factor (Q) Calculator

Calculate series and parallel RLC circuit natural resonant frequency (f0 = 1 / 2π√LC), Quality factor (Q), -3dB bandwidth (BW), and characteristic impedance (Z0).

Calculation Results

Natural Resonant Frequency (f0): 495.17 kHz Angular frequency ω0 = 3.11 × 10⁶ rad/s
Quality Factor (Q): 14.62 Underdamped System (Sharp resonance peak)
-3dB Passband Bandwidth (BW): 33.87 kHz (Passband: 478.2 kHz to 512.1 kHz)
Characteristic Impedance (Z0 = √(L/C)): 146.16 Ω

About This Calculator

Calculate series and parallel RLC circuit natural resonant frequency (f0 = 1 / 2π√LC), Quality factor (Q), -3dB bandwidth (BW), and characteristic impedance (Z0).

Frequently Asked Questions

What happens at resonance in an RLC circuit?

At the natural resonant frequency (f0 = 1 / 2π√LC), inductive reactance (XL = 2πfL) exactly cancels capacitive reactance (XC = 1 / 2πfC). In a series circuit, impedance drops to its minimum pure resistance (Z = R), maximizing current flow.

What does Quality Factor (Q) signify?

The Q-factor measures the ratio of energy stored to energy dissipated per cycle. A high Q-factor (> 10) yields a sharp, highly selective frequency response ideal for radio receivers, while a low Q yields a broad, lossy response.

What is the relationship between Q-factor and bandwidth?

Bandwidth is inversely proportional to Q: Bandwidth (BW) = f0 / Q. Doubling the Q-factor cuts the -3dB bandwidth in half, providing tighter frequency filtering.

Why does the Q formula invert between series and parallel RLC?

In a series circuit, higher resistance increases damping and lowers Q (Q = √(L/C) / R). In a parallel circuit, higher parallel resistance reduces bypass dissipation and increases Q (Q = R / √(L/C)).