Re: [CAD_CAM_EDM_DRO] Re: floating aluminium

info.host@... wrote:

> MRI's need to be super-cooled? He he he, they'd look much better that way
> with the fluid mystically boiling off in big clouds. I heard of a team
> managing to put together a super-conductor that works very close to room
> temperature, there was even one in Focus that claimed to have one at room
> temperature and was investigating it to be sure. How is there such a massive
> current/field at zero volts and zero ohms? I mean, why is there any force on
> the electrons to move if there is no difference from where they're at and
> where they're going?

One of the mysteries of physics! And, in fact, they really don't understand
it very well. The classic 4-9 K superconductors were thought to be well
understood, but they just came up with a new superconducting alloy that
has a critical temperature higher than anyone though possible for that class
of superconductor. The "high temp" superconducting oxides are not fully
understood, but progress is being made.

> I take it electrons have to move through some
> resistance to produce a magnetic field

No, they don't. Electric current (either electrons, protons or their anti-particles)
need to move in space to create a magnetic field. That is all that is required.

> or else capacitors would be
> incredibly big magnets wouldn't they?

No, they won't, as a capacitor stores CHARGE, and doesn't particularly
organize the motion of the charges. When it is charged up, it holds the charge,
but the charge carriers are NOT moving.

An electromagnet is designed to organize the movement of charge carriers
so that their magnetic fields add up constructively to a large field.

> In school we did a thing about
> magnetism, as well as those damned elastic bands, and we listed one of the
> factors affecting it as resistance in the wire.

The current in the circuit IS affected by resistance. But, the resistance does
not affect magnetic field, only the current. If the circuit has more resistance,
you need to supply move voltage to get the same current.

Jon