As a follow-up of this thread I took a 3000 pF capacitor and charged it
to 100 V from a power supply. Then I discharged it through a wire loop,
approximately a circle whose diameter was 20 cm. A small portable radio
set, tuned to a weak station, was placed about 1 meter away from the
center of the loop (close to the axis). Clear clicks were heard each
time the capacitor was discharged. The wire, whose cross section is close
to 1 mm^2, was isolated; I was holding it in my hand.
I find this puzzling because the electrostatic energy is 15 microjoules.
If the "what happens to this electrostatic energy" question was answered
correctly then only 0.00056% of our 15 microjoules (that is only 84 nJ)
should be emitted. And only a very small fraction of this would actually
be intercepted by a short antenna (about 1 inch) inside the 5-inch-long
radio set. A signal of that energy, in my opinion, would be much smaller
than the noise. But cleaks were heard clearly above the noise level.
I suspect that another mechanism, compeeting with the magnetic dipol
radiation, must be at work here. What can this mechanism be? What
evidence do you have to support the answer?
Ludwik Kowalski