Natural Science Forum / Physics / Electromagnetism / October 2005

$       Feynmann's *virtual particle* NEGATiVE-COUNTs, duh.!!
AMBiENT MEDiA does NOT require "virtual particle" *NEGATiVE-COUNTs*.!!
A *Zero-AVERAGE* of particle-COUNTs requires *some-NEGATiVE COUNTs*.!!
                                     brian a m stuckless

Can anyone tell me what is the change of the phase of an EM plane wave
by reflection from a mirror. Does it depend on the incidence angle - if
yes what is it by 45 degree.
I read that it is PI but i'm in trouble with a physical problem and

Sorry for the crossposting, but I didn't quite know where to send this.
I had a weird experience yesterday and I was wondering if this is
physically possible or if a few screws temporarily got loose in my
head.

Reading some books I found that there is nothing about the mechanism
the magnetic field is spred in the distance of the ferromagnet (like
iron). I suppose that the domains rearrange where the outer magnetic
field is applied and than they form a new magnet which rearanges the

Anybody know where I can find information on AC losses (hysteresis,
etc) in superconductors? I'm especially looking for something that
would tell me what the losses in MgB2 and carbon doped MgB2 would be at
very high sweep rates (eg 1000-10000 T/s).

I am developing a FDTD simulation software and get problems calculating
the near-to-far-field transformation in the 2D TE-case. Searching the net
I found the following post to sci.physics.electromag from 6 Feb. 2004:
opticslayman schrieb:

I need a source of above-UV or near x-rays that must be able to look
through the black plastic of electronic components. the object is
checking wafer visually, no high resolution is needed, we only want to
know the position of the wafer (GaAS 0.2*0.2 mm) in the device. It is

I'm looking for people who tried to put lumped elements to fdtd codes.
I have quite big problem with that.
Now i want put the RC or RL filtr. I checked the enter impedance and
it's good, but the transmission (Uc/Urc) is not good and I dont know

I wrote in my post
http://groups.google.com/group/sci.physics.electromag/browse_frm/thread/3f2d4492
bb6e5035/698366bd4ace6bc7?q=khrapko&rnum=1&hl=en#698366bd4ace6bc7
that the standard canonical spin tensor, which is used by physicists,
leaded to incorrect results. For example, spin ...

$             It's had it's day.!!
jOHN Baez ..on sci.physics.research (s.p.r.).!!
S.p.r. MODERATORs are NOT keeping out CRANKs.!!
Average QUALiTY of POSTs DROPPED since he left.

Suppose you have a blackbody at temperature T and a pure low-density
gas at the same temperature. For T, the blackbody radiation spectrum
can be plotted using Planck's theory. I understand that the spectrum of
the gas is zero for all wavelengths except for certain "emission

I'm currently taking course in microwave engineering (and maybe I
should already know this) but, what exactly is the difference between
the wavenumber k and the propagation constant beta.  Is it that
k=w*sqrt(permeability*permittivity) and beta is the real part of k

Frame-of-Reference ..SPEED versus VELOCiTY:
VELOCiTY vector A->B straight from POSiTiON A to B, as shown;
o o                         o  o
    o                   o        o       vector

This is a question about electric multipoles, and multipoles in general,
that has really been bugging me. Theoretically, how would one construct a
multipole where the first nonzero term was the "16-pole" term? What is the
simplest, most symmetrical way to construct such a ...

The force on a current-carrying wire in a magnetic field is shown in many
books (F=Bil). It is usually depicted as a wire between poles of magnet all
in a medium of air. I was wondering if the linearity of F=Bil still holds in
a non-linear magnetic environment?