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Bandwidth
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Frequency range around resonance.
Δω = R/LThe width of the resonance curve between half-power points: Δω = R/L = ω₀/Q. A narrow bandwidth gives selectivity.
Radio station selectivity.
Trade-off with response time.
In more detail
The bandwidth of a resonant circuit is the range of frequencies over which the power is at least half its peak value. It equals ω0/Q, so higher Q gives narrower bandwidth.
Real-world uses
- Radio channels are chosen to fit within a bandwidth.
- Filter design sets bandwidth to pass or block frequency ranges.
- Radio receivers have a bandwidth that sets how many stations can be separated without interference.
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Frequently asked questions
Why is bandwidth important?
It determines how many stations or signals can be separated.
How does bandwidth relate to Q?
Bandwidth equals resonant frequency divided by Q.
How is bandwidth related to Q?
Bandwidth equals the resonant frequency divided by Q, so a higher Q gives a narrower bandwidth.
Related topics in AC Circuits & EM Waves
Phase angle · Series resonance · Quality factor in LCR · Power factor · Wattless current · LC oscillations