A bunch of questions regarding radially magetized ring magnet.

[Magluvin]

I've never head of speaker motors before now, are they some sort of actuator?

Do you have a link?

Look at the pics of speakers above on previous page. The magnet, plates, center pole and coil mounted to the cone. Speaker motor. Piston action without the crank shaft.

Mags

[Low-Q]

Making a radially magnetized magnet is quite simple. If you have a ferrite magnet for speakers, you simply place a coil on each flat surface. These coils must repel each other when current flows through them.
This way you destroy the axial field in the magnet, and create a radially magnetized field in it that will sustain after you remove the coils.


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[lancaIV]

         Has the FEMM-program the TMR-Effect included ?

              https://www.google.pt/search?q=TMR-Effect&ie=utf-8&oe=utf-8&client=firefox-b&gfe_rd=cr&dcr=0&ei=LQWtWfn_FMap8we1ooWwAg

     Attention: learn to use the wikipedia-lexikons correct !

     f.e. compare the content
     a. https://de.wikipedia.org/wiki/Magnetischer_Tunnelwiderstand
     b. https://en.wikipedia.org/wiki/Tunnel_magnetoresistance


    if become translated by the different automatic language tools
    do not expect to get an 1:1 translation,

    probably positive mind will get a "negative aura" : chaotic

You ever heared about him,  THE LAST german UNIVERSALGENIUS :
https://www.google.pt/search?q=carl+friedrich+august+von+weizsaecker&ie=utf-8&oe=utf-8&client=firefox-b&gfe_rd=cr&dcr=0&ei=fQqtWeLpL5DY8geP3r3QAg

http://www.spiegel.de/wissenschaft/natur/carl-friedrich-von-weizsaecker-tod-eines-mahners-und-vordenkers-a-480059.html

http://www.faz.net/aktuell/feuilleton/carl-friedrich-von-weizsaecker-synthesen-eines-jahrhundertmannes-1438060.html


                      learning by showing and doing
      https://pt.wikipedia.org/wiki/Pit%C3%A1goras
Segundo os pitagóricos, o cosmo é regido por relações matemáti
             

[PolaczekCebulaczek]

Interesting speaker stuff here... but before I start  making my magnet I want to ask another important question, that is: what would happened when radially magnetized ring is rotated while compass is inside the ring(1)? would a compass needle rotate with ring or not? (needle just stay at position where I put it) and what if compass is off the center, closer to one edge than another? (2). Please see diagrams below.

[Low-Q]

These magnets or speaker magnets does not have a field gradient along the circumference. So there will be no interaction between the rotating magnet and the compass needle.
This statement is only true if the magnet is uniformly magnetized. Most magnets are not that precicely manufactured.
So in a practical experiment you will probably se some movement in the needle.


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