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A capacitor and a coil are charged in the LC circuit. When the circuit switch is closed, the current starts to flow. In theory the oscillations and the current do not deteriorate, but why in reality the current amplitude fades to zero?

I know that all the components (coil, capacitor and the wire) have resistance and that's why the currents starts to fade to zero. But are there any other reasons too?

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I know that all the components (coil, capacitor and the wire) have resistance and that's why the currents starts to fade to zero. But is there any more reasons?

If the circuit is well-constructed, the resistive loss will be the most important way energy is lost and the oscillation decays.

If you made the circuit sloppily, with a large loop of wire between the components, that loop of wire could act as an antenna, radiating energy into space, which would make the oscillation decay more quickly (conversely, if there was incoming radiation from some other source, at the correct frequency, the interconnect wires could act as a receiving antenna and deliver energy to the LC circuit, starting up or sustaining the oscillation).

Or if you electrically or magnetically coupled (by the arrangement of the interconnect wires) your LC circuit to some other structure or circuit, you could conceivably couple energy out of the LC circuit by near-field effects and again speed up the decay of the oscillation.

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