I don't suppose Tesla coils have practical applications. (?)Aside from easily generating high voltages easily - the principles incorprated in a Teslas coil are embodied in every day items -
- in that tuned circuits where primary and secondaries are linked by magnetic flux/a magnetic field are incorporated in everyday AM and FM broadcast radios and their transmitters to automotive (spark) ignition systems (even though the secondaries of the coild are *not* strictly tuned, they do 'ring' owing to the stray interwire capacitance that exists in any physcial coil).
Yep. Although I don't work on the automotive side (I do marine ignitions), the principles are the same. About the only thing we watch for besides turns ratio (and making sure the wire insulation has a high enough dielectric) as far as the secondary is the inductance, because too high of an inductance serves as a rev limit due to saturation at high RPM.
What's real fun is to hook a marine ignition (cap ripper @ 250-300VDC output) to an automotive coil (rated with a 12VDC primary, and thus a higher turns ratio). The coil don't last long when you do that, but it is fun to see foot-long sparks!