[time-nuts] Re: in-ground clock room

[Dana Whitlow]

It may be that the time constant of eddy current damping would be too
limited by the
inavailability of sufficiently good conductors (ar room temp, anyway).  To
get really
long time constants one basically needs superconductivity somewhere in the
system.

Dana


On Sat, Sep 11, 2021 at 11:54 PM Tom Holmes <tholmes at woh.rr.com> wrote:

> Which suggests a possible damping mechanism.
>
> From Tom Holmes, N8ZM
>
> > On Sep 11, 2021, at 10:08 AM, Adrian Godwin <artgodwin at gmail.com> wrote:
> >
> > Doesn't that depend on the configuration of the fields ?
> > For instance, a pair of facing like poles will repel and, as you say,
> make
> > a good spring.
> > But a magnet falling down an aluminium tube will go slowly, because of
> the
> > generated eddy currents and their subsequent fading due to the lossy
> > aluminium.
> >
> >
> >> On Sat, Sep 11, 2021 at 2:02 PM Poul-Henning Kamp <phk at phk.freebsd.dk>
> >> wrote:
> >>
> >> --------
> >> Gilles Clement writes:
> >>
> >>> Magnetic levitation, dampening external vibrations ?
> >>
> >> By theselves magnetic fields are just really good springs.
> >>
> >> To get any kind of dampening you either need to add a
> >> dash-pot (=shock-absorber) as a dissipative device or
> >> you need to modulate the magnitic field to emulate
> >> the same result.
> >>
> >> I'm told the latter is much harder than it sounds.
> >>
> >> --
> >> Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
> >> phk at FreeBSD.ORG         | TCP/IP since RFC 956
> >> FreeBSD committer       | BSD since 4.3-tahoe
> >> Never attribute to malice what can adequately be explained by
> incompetence.
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