ENERGY AMPLIFICATION

[MileHigh]

https://www.youtube.com/watch?v=rtDAK7Umk7A

...nor Daniel...

[Dave45]

Knock Knock Knock its dave
I got the goods open up
Lol

Dave's not here
lol

Thanks MH I needed a laugh 

Thats what I feel like talking on this forum

[MarkE]

Lol

Why does a coil pulsed with dc give an ac signal back

neg pulse pos return

or pos pulse neg return

expanding magnetic field - collapsing magnetic field

A coil pulsed with a voltage does not necessarily give AC back.  How the coil behaves all depends on the switching circuit connected to the coil and the parasitics around that switch or switches.  In an idealized configuration, the current smoothly transitions from the path through one switch to the path through another.  Clean hard switching circuits manage this without ringing as do soft-switching configurations.

[MarkE]

We use the term magnetic field but actually its its the electric field that collapses into the coil.

In low frequency situations we can talk about separate electric and magnetic fields.  In those cases it is most definitely the magnetic field that decays when by either increasing the external impedance and/or reducing the applied voltage in the direction of the current flow we decrease the current flow towards zero, and/or continue through zero to reverse the current.

[a.king21]

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