Gremlin wrote:
"Commander Kinsey"
news alt.computer.workshop, wrote:

https://youtu.be/J9b0J29OzAU

That's cool. Thanks for the share. I'd be interested to know if you can
explain how you think it works, without cheating, that is.

Pretty simple really. You look it up.

https://www.first4magnets.com/blog/h...using-magnets/

*******

The video is a bit deceiving, and to my eyes,
there's not much of a hint that the wire is
conducting. It does not look like shiny copper
wire, nor like tarnished copper wire. It's
"just a coil of something". There is no hint what
the material is. Why is that ? They've adjusted
the colour of the video (colour corrected to an unnatural
balance).

We live in a sad age. The age where we've forgotten
how to coat the outside of copper wire with nickel.
Using nickel, the contact properties of our coil
would be "excellent". If you use copper alone, it's
going to spark like a pig, or, the little train
will stop half way through the demo.

If it worked as stated, based on your experience
with copper conductors and electricity -- it should
throw sparks as the ends of the purported
projectile circulates. Yet we don't see any
sparks. Why is that ? A coil section that small,
there's going to be 500mA to an ampere of current
in the coil. There should be decent sparks.

When I was a kid, my uncle made me an electric
motor. Pieces of Iron wire in a bundle, was used for
cores. Enameled copper wire for the windings. The design
style is an "open frame", in other words, the worlds
most inefficient electric motor. It's a wonder these
rotate at all, but they do. (You sometimes have to
give them a flick with your finger, to get them running.)
More compact motors work much better, ones where the
magnetic pole pieces are continuously presented to one another.
There is "too much air" in these motors.

http://inventorartist.com/wp-content...GuyOrg-600.jpg

And the noteworthy part of the little motor,
was the sparks it would throw as the armature made
contact with the bared copper wires touching it. We
didn't use plates or springs or carbon brushes.
Just bared copper wire. You got a nice stream of
blue sparks as it rotated. And a bit of a sound effect.

Yet none of that is visible in the video, and
you have to wonder whether there is just a magnet
under the table and an accomplice.

If they wanted to impress us, their "table" should
have been a perspex sheet.

*******

When the copper coil has the ends touched together,
the battery and magnets continue past that section.
That can only happen, if the copper makes *excellent*
contact, between the two ends of the coil. Normally,
you would need to solder a copper coil ends like that
together, so the projectile would go round and round.
Yet, the demonstrator has no trouble at all, getting
his protege to jump the gap. He is able to hold
the ends of the copper wires together well enough,
so it can handle a relatively high current.

Their copper wire is "amazing". Never an ohmic moment.
I bid 300 quatloos for the copper wire used...

I would also like to know how they adjusted the
colour in the video, to suppress blue sparks. Was the
camera fitted with a filter, or were the sparks
removed in post ?

Paul