special magnet setup question

[mcorrade]

If I take a n50 rectangle neo magnet which has it's north and south on the ends, and I place it in a small steel tube that fits tightly around the magnet and the tube is just a bit longer will this change or intensify the flux? If I take the same tube and close off one end with the same magnet in it will this change the field/flux....

crude picture attached

[gyulasun]

If I take a n50 rectangle neo magnet which has it's north and south on the ends, and I place it in a small steel tube that fits tightly around the magnet and the tube is just a bit longer will this change or intensify the flux? If I take the same tube and close off one end with the same magnet in it will this change the field/flux....

crude picture attached

Hi,

Your first question: yes, your steel tube (assuming it is a magnetizable steel) will change the flux significally around the whole permanent magnet,  the flux will be reduced.
Your second question: yes your closing off one end, it will further reduce flux at that end.

See this link: http://peswiki.com/index.php/Director:Hilden-Brand_Electromagnet_Motor and go down to about half-page to see title Hilden-Brand electro magnetic valve.  You may see some discussion on Jack valve on this Forum as well.

[mcorrade]

Great thanks for the answer and the link. It wasn't the answer I was looking for but it saved me a lot of time.
So with that, if I use a non metallic tube it shouldn't upset the field correct. What about materials like brass or aluminum?

thanks     

[gyulasun]

Great thanks for the answer and the link. It wasn't the answer I was looking for but it saved me a lot of time.
So with that, if I use a non metallic tube it shouldn't upset the field correct. What about materials like brass or aluminum?

thanks     

Yes, in case of nonmetal tubes the flux from the magnet remains unchanged.
With metal tubes which are non magnetic but conduct electricity, you have to consider two cases:
1) when the metal tube is stationary and the magnet also stationary inside the tube
2) when the metal tube moves (or the magnet moves with respect to the tube)

In case 1, the flux does not change
In case 2, the motion induces eddy currents in the metal tube so most of the magnet flux is used for heating the walls of the tube  (see this interesting link too: http://www.16pi2.com/eddy_currents.htm )

(flux lines from the magnet interact with the flux lines created by eddy currents)

see also http://www.physics.brown.edu/physics/demopages/Demo/em/demo/5k2025.htm
or for aluminum sheet: http://youtube.com/watch?v=-7IzlnFH7ww&feature=related

[libra_spirit]

Your question is basic, but there is an effect from this possible not often observed.

The magnetic field will pass through the iron tube in a magnetic aiding attraction, and this is like having two magnets in attraction.

If you now place a copper tube between them, between the magnet and the outer iron layer, you will get an effect from the precession field of the magnet. A magnetic field is not a static or stationary entity, but actually precesses at a microwave frequency.

This generates a DC "A field" off the sides of the magnet.
Place another copper tube around this and the outer A field will oppose the inner one.

You will now start to create a very strong "torsion field" as the two opposing A fields come together along the blotch walls of the magnetic fields. This field is strong enough to alter the weather in tubes of about 4 foot long. The torsion field can be strengthed by adding bismuth to the core.

Here is the device:

http://magnetism.fateback.com/Tube_Device.htm

Here is a study of effecting the weather using these kind of devices in Autsralia:

http://magnetism.fateback.com/OZ.htm

Check out the pic at the bottom where two of these are used in a crossing format to link earth energy and alter rain effects at a given distance away.

It has been observed that tube devices may encourage rain big time, if used in dry parched areas of the world.

Dave L