once again about plasma

Hi Would that be a magnetic field or an electrical field ?

John

hi John

I mean a magnetic field, I think that in reality there should be a cathode close to the plasma [as much as the high temperature will allow!] attached to the positive pole of a magnet,and the electrons will flow to the positive pole but doing all the electric circuit.

Right, the ions would be driven by the electric field with or without magnetic field. The magnetic field would just deviate the ions during their travel.

Dear Guest,

If you don't know too much about plasma then this answer may not make to much sense! Firstly the short answer - IT DEPENDS! By and large it depends on the type of plasma - of which there are many types! If we consider a gas plasma ie plasma created by adding electrical energy to a gas then surrounding it with a magnetic field the answer is no!

Particle movement ie Ions electrons etc is really quite complicated within a plasma - overall a plasma can be considered quasi-neutral! There are several thermal and electrical subsystems within a plasma so to ask your question in a way doesn't make sense unless you put it in context.

For example to surround a low temperature plasma with a magnetic field broadly speaking would result in two different phases; ions parallel to the magnetic field, and second ions perpendicular to the magnetic field but no current would be created!

All plasmas by their nature are electrically conductive - if you want to conduct electricity then you must create a potential difference! So hope this helps! Depending on what you want to do the best way to conduct electricity is through a wire! Good luck!

Rogerzz

You are incorrect. In a gas plasma subjected to an electric fields, the ions are separated by charges. The +ve move in one direction while the -VE move in the other. Of course, they are still agitated by thermal effects but their average displacement is toward the oppositely charged electrode. The lighter electrons will move much faster than the atoms nucleus. This can create a positively charged plasma as the electrons are absorbed in the electrodes.

As correctly pointed out by one of the guest, the magnetic fields will simply curve their path toward the electrode.

The question was whether if a magnetic field was applied to a plasma it would cause an electrical current to be generated! Given the broadness of the nature of plasmas and the unspecific nature of the question I replied in general terms! I said it wouldn't!

None of the information in my post is 'incorrect'! Perhaps you could be specific about what part of my post you consider incorrect - at least then it would be possible to be discussing the same topic and then perhaps you could provide an appropriate answer to the question?

Rogerzz

Sounds like your talking about a tokamak reactor - http://en.wikipedia.org/wiki/Tokamak

Do a Google search on magnetohydrodynamics. You can generate power using a flame and an electromagnet, but it's not very environmentally friendly.