A vibration-capable, electric connection of a coil L, and a capacitor C, forms a resonant circuit. Initially, the capacitor charges. The resonant circuit stores electrical energy in the electric field of the capacitor. Now a current flows through the coil, whereby a magnetic field is established. The electric field will have completely degraded when the magnetic field has reached its maximum strength.
Since there is now no electric field present, current can no longer flow – but according to Lenz’s law the “power loss” now affects the coil, and in turn further drives the current in the same direction. The magnetic field is completely dissipated by this. Driven by the magnetic field of the coil, the current once again charges the capacitor. If the magnetic field were to be reduced , the capacitor would have a maximum electric field – but with opposite polarity compared to the beginning.
Now the charge is, once more, stored in the capacitor. The electric field breaks down, and at the same time, a new magnetic field builds up. The field line pattern is now the other way around. The new magnetic field drives the current further, breaks down itself, and re-charges the capacitor to the state it was in at the beginning of the observation. There is a permanent exchange between electric field and magnetic field.« Back