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RLC Sine Wave Clarification

  1. Dec 12, 2012 #1
    So I'm trying to get my head around RLC circuits and what is happening

    say we have a 10 ohm resistor, 1000uf capacitor and a 10H inductor in a circuit powered by a 10 volt source.

    Is the resulting oscillation of the sine wave frequency the result of the inductor resisting the flow of electrons(for a fraction of a second if even) and the capacitor spilling some of its excess charge to compensate for this delay to keep the circuit powered??
  2. jcsd
  3. Dec 12, 2012 #2

    Is the circuit series or parallel? If parallel, does it have a branch for each circuit element, or is the resister in series with the inductor or capacitor. Is the voltage source a step voltage, ramp, triangle, or sinusoidal? Maybe you better produce a schemat.

    Have you studied RLC circuits? From the question you asked, I don't think so. There is plenty of material in texts and the web describing them.

  4. Dec 12, 2012 #3


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    The resulting oscillations is a result of the reactive elements (the capacitor and inductor) storing and discharging energy at a frequency dependent rate. The amount of damping to the oscillations is provided by the resistance. In a system with no resistance, which is only theoretical, oscillations would persist.

    What happens is that with a sinusoidal input, current will cause a storage of energy in the inductor, in the form of a magnetic field will the sin wave is "increasing", as it falls, the field collapses and induced voltage into the inductor, which in itself causes flow external to the inductor and to the capacitor, to be stored as an electric field across the plates. Once it's potential difference is higher than the source, however, it itself acts like a source. It acts to transfer energy back to the inductor, and the cycle repeats. One can see how the oscillations occur. A small resistance, and optimal component values combined with frequency can lead to large resonance.

    Very basically..
    Last edited: Dec 13, 2012
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