we all stood mesmerized as we watched huge, gigantic
bolts of electricity fling themselves out from the surface of the sphere
and immense fingers of purplish-blue reached out to the grounding lamppost
off to the right. the column from the center of the coil blasted out
hurricanes of air as generators spun themselves into a mach 1 frenzy. greg
stood inside the sphere of the tesla coil with a metal probe, taking more
measurements and logging the results. as i watched this behemoth of
electricity and the man inside, i was only sure of one thing... this guy
must be abso-fucking-lutely insane.
the lightning continued for about five minutes until
the operator powered the generators back down. finally, the noise and the
ozone and the light subsided to a point when everyone could snap out of
their tesla-induced hypnosis. still alive inside the sphere, greg used his
bullhorn to explain the concept of the faraday cage.
"faraday cages are named after michael faraday, a
british physicist who came up with faraday's law of electromagnetic
induction. the faraday cage can be thought of as a closed-circuit, like
this cage that i'm standing in or the metal cage of your car. the
time-rate of change of magnetic flux within a completely closed physical
circuit has to equal zero. the shell of the sphere acts to distribute the
electromagnetic force over the sphere, creating a physical force field."
the geeks in the audience all nodded to each other and giggled, as if a
dirty joke had just been told. everyone else continued to stare at the man
in the cage.
"in other words," he continued, much to the relief of
the majority of the audience, "the electricity flows over the sphere
because the metal shell of the sphere makes a closed circuit. electricity,
when given the option, will always take the path of least resistance, so
to close the circuit, it'll travel over the surface of the sphere rather
than through it. if i ever stick any part of my body outside of the cage
while the coil is on, then i will be considered a part of that circuit. if
i become part of the circuit, everything will start smelling funny."
"this," he explained, "is the reason why people in
cars don't get hurt by bolts of lightning."
it was right then and there that i decided that this
was why i needed to name my next car faraday.
future | retro