Re: Danger, and I don't understand why.

Tesla List wrote:

> I tried to repeat this "occurence" and found that the wires would only
> spark when pulled apart if they had first SHORTED WHILE ARCING with
> the power on, and it was then turned off before pulling the wires apart.
> The spark produced quite a snap but is no where near like a cap
> discharge,  more like a spark-plug type click.

Shorted inductors store energy as well as capacitors in open circuit.
If the input connection of the transformer is opened when there is a
significant current in the transformer windings, the secondary current
will first increase somewhat, as the energy stored in the primary
is transferred to the secondary winding, and then will decay
with a time constant L/R, where L is the inductance of the secondary
and R its resistance. This may leave significant current circulating
for a few seconds, and if the short is opened, the large inductance
of the secondary will force the current to continue, increasing
the voltage at the terminals as necessary for a spark.

Antonio Carlos M. de Queiroz