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Question on plasma physics

  1. Mar 13, 2013 #1
    Hello all,
    I've been examining plasma physics and electricity (or at least trying to with a search engine) and have a few questions.

    1. Can plasma be polarized? For example, if a magnet is placed with the "north" polarity near a magnet, will it maintain that shape?
    2. If a wire carrying an electric current is heated, will it produce a higher current (more electricity)?
    3. What happens to free electrons when they are confined in between two magnets of differing polarities? Same polarities?

    These are not homework questions, just questions of my own i'd like answered.
  2. jcsd
  3. Mar 14, 2013 #2


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    2017 Award

    Staff: Mentor

    Which magnet? Which shape?
    A wire does not "produce" a current. Most wires increase their electric resistance if you heat them, so the current will usually drop if you heat the wire. There are some exceptions, however, where resistance drops with temperature.
    They are not confined in anything. And they are not free, as they are in a magnetic field. They will feel the Lorentz force.
  4. Mar 14, 2013 #3
    "if a magnet is placed with the "north" polarity near a magnet, will it maintain that shape?" "

    What do you mean by this?
    Well a plasma is a state of matter in which a gas is ionized that means that the electrons are now separate from the nucleus which turns the plasma into a conductor and also it reacts strongly to magnetic fields and the flow of plasma creates it's own magnetic field because the electrons have a negative charge and the nucleus a positive one.


    have a look at that , kinda explains the basics.

    As mfb said wires usually increase resistance when heated so for a given current the current will drop and some of it will be dissipated as heat.Remember that basically under normal conditions every conductor like an ordinary wire or pcb circuit or anything else is a resistor , small one but still it has resistance and that resistance drops the current and heats up the conductor.
    That's why they need all that liquid nitrogen etc cooling for superconductors.But that has to do with the atomic substructure of the wire under these temperatures that makes it a ideal conductor.If you want to see that read up on google about superconductors.
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