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LC oscillations
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Energy sloshes between E and B fields.
ω = 1/√(LC)Charge in an LC circuit oscillates at ω = 1/√(LC), energy sloshing between E in the capacitor and B in the inductor; resistance causes damping.
Radio transmitters.
Analogous to a mass on a spring.
In more detail
An ideal LC circuit oscillates with energy shuttling between the capacitor and inductor at ω = 1/sqrt(LC). Adding resistance causes damping, and the oscillations gradually decay.
Real-world uses
- Tuned circuits in radio transmitters use LC oscillations.
- Clock generators in electronics use LC resonators.
- Engineers designing oscillators for radio transmitters use LC circuits, where energy sloshes between the coil and capacitor.
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Frequently asked questions
Where is the energy stored?
In the electric field of the capacitor and the magnetic field of the inductor.
Does the energy stay constant?
In the ideal case yes, but resistance causes losses over time.
Does the LC oscillation stop?
Only if there is resistance. An ideal LC circuit oscillates forever, while real circuits lose energy as heat.
Related topics in AC Circuits & EM Waves
Bandwidth · Power factor · Wattless current · Parallel resonance · Filters · Transformers in power transmission