Magnetic wheel by steel shielding

[nix85]

Taken from great doc always worth rewatching

https://www.youtube.com/watch?v=bht9AJ1eNYc

[onepower]

Nix85

Coil repelled by a rock
https://www.youtube.com/watch?v=muJqtz-ECfg

Mad science... that's a pretty cool video.

Superconductors are the best material to repel a magnetic field and because the free electrons in them experience no resistance they immediately produce induced eddy currents as a counterforce to any external magnetic fields.

I found the effect can be reproduced using a neat setup. If a neodymium magnet is dropped onto an aluminum plate the moving magnetic field induces eddy currents in the aluminum which oppose the motion of magnet. However if the aluminum plate is vibrating the moving aluminum plate produces the same effect as a moving magnet because the motional effect is relative.

So we can move the magnet or a conductive material and produce a similar effect. In effect it's not the material but the moving free electrons in it which produce the effect. Logic would suggest the material with the most free electrons and the least resistance would be the best material to oppose any external magnetic fields. The greater the number of mobile electrons the greater the induced current counterforce, the lesser the resistance the more efficient the effect.

Regards

[nix85]

Nix85
Mad science... that's a pretty cool video.

Superconductors are the best material to repel a magnetic field and because the free electrons in them experience no resistance they immediately produce induced eddy currents as a counterforce to any external magnetic fields.

I found the effect can be reproduced using a neat setup. If a neodymium magnet is dropped onto an aluminum plate the moving magnetic field induces eddy currents in the aluminum which oppose the motion of magnet. However if the aluminum plate is vibrating the moving aluminum plate produces the same effect as a moving magnet because the motional effect is relative.

So we can move the magnet or a conductive material and produce a similar effect. In effect it's not the material but the moving free electrons in it which produce the effect. Logic would suggest the material with the most free electrons and the least resistance would be the best material to oppose any external magnetic fields. The greater the number of mobile electrons the greater the induced current counterforce, the lesser the resistance the more efficient the effect.

Regards

That was my guess, that rock is metallic and conductive and eddy currents repel the coil. But then why just when coil is first pulsed and then nothing. They are feeding it AC as i understood.

It's not a Meissner effect for sure as superconductor expels but not repels the field.

"However if the aluminum plate is vibrating the moving aluminum plate produces the same effect as a moving magnet because the motional effect is relative. So we can move the magnet or a conductive material and produce a similar effect."

Not sure what exactly you meant by "produce a similar effect". You mean that neodymium's fall is not slowed down by vibrating aluminum?

It instantly reminded me of that navy patent on superconductive room temperature wire vibrated by ultrasound.

[nix85]

Here is another video of the same material, it seems it attracts magnet a bit, at least on the ends.

https://www.youtube.com/watch?v=SQw-nk6nYs0

[Floor]

1.
Although one is a noun (a thing) and the other is a verb (an action), energy and change,
these two words are almost synonymous.   

Energy exist everywhere known.
But its existence is as a potential, until it is expressed, and some change occurs.
When energy is expressed / manifested / when is acts, it becomes a force.

Generally that force is in the form of a push or a pull.  It may be mechanical, magnetic,
electrostatic, gravitational or so on.

When energy acts, change occurs. 
There is no way to either measure or know what energy is, except as the change or
changes it causes. 

We may in many instances, because of prior experiment, know the potential energy
in some relationship, but we cannot witness nor measure that energy except as some
change that occurs.

Energy is not energy until it manifests as a force and is causes some kind or another
of change.
Until it acts it is only potentially energy, or potential energy.

Potential energy is not expended nor transformed nor wasted.
...................................
2.
When energy manifest / acts, the change that occurs (as far as is known) is either a
transformation of that energy into another form of energy, or a transfer of that energy,
or both, transfer and transformation. 

Example..

A cue ball strikes another ball. Some of the kinetic energy in the cue ball TRANSFERS
to the other ball. The other ball moves.

But there is also a click sound as some of the energy was TRANSFERRED  to the air and
became sound
(sound is a form of kinetic energy).

Also some small amount of the energy was "transformed" into heat
(although heat is a disordered form of kinetic energy).

But also some very small amount of the energy was  TRANSFORMED into
electromagnetic waves.
..............................
3.
Direction (as in toward or away from).

The direction of the interactions between two or more interacting objects or bodies
is a major factor in that interaction.   This is why forces are described in terms of
both magnitude and direction (as vectors).

Example...

Rolling a bowling ball along a level surface required no work against gravity.
The DIRECTION in relationship to gravity's pull matters.

Except that, friction between the bowling ball and the surface would not be present
if not for the weight given to the bowling ball by gravity's force. 

Otherwise (as long as the surface is level) it requires no work, either against or
assisted by gravity to roll the bowling ball.

Energy is expended to overcome the inertia of the ball.

If the surface is not level, but otherwise flat, one may expend energy against gravity,
be assisted by gravity

                           or...

again be unaffected by gravity in rolling the ball.  This would be moving the ball as
either,
up hill,
down hill
              or
at precisely 90 degrees to the direction of the surface's incline (gravity neutral).
...........................
3.
Magnets can be force neutral to one another in a manner similar to that of a ball and gravity.

That force neutrality is direction specific.

Energy is expended in relationship to a force, when we act either toward or away from the
direction of that force, but not when we act at 90 degrees to it (mostly).

floor