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Protons in a positive magnetic field

  1. Jan 21, 2012 #1
    What would happen if I were to set up two extreamly powerful magnets one above each other. Say the strength of each magnet was about 30 tesla. If both the magnets were positive and repelled each other with extreme force, if protons were in the middle of this repelling field, could those protons "explode" if there was enough pressure? When I say explode, I mean like explode like they do at the LHC in the proton-proton collision into many subatomic particles.

    I dont know anything about physics because I haven't taken it yet in school but I am curious as to what would happen if such an experiment were implimented. All answers are appreciated.
  2. jcsd
  3. Jan 22, 2012 #2

    Simon Bridge

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    1. you are thinking of an electric field - the magnetic field would deflect a moving proton and magnetic poles are N or S not + or -.
    2. the fields do not act like a pressure or a wind which may squash charges
    3. if the proton were exactly in the middle, so it it would be in a place of zero field - so no forces, like in the eye of a storm.
    4. protons split in p-p beam collision due to the strong nuclear force rather than the electromagnetic. They don't "split" into "many" subatomic particles in LHC - they've only got three quarks each and they start out as subatomic anyway.

    So - the likely result of shooting a proton dead-center in a gigatesla magnetic field would be nothing. Well - reorient it's magnetic dipole as in stern-gerlach experiment.

    Quarks have charge so I suppose technically it may be possible to make an electric field strong enough to appreciable oppose the strong nuclear force but I shudder to think what that would be like. You still wouldn't pull it into individual quarks. Not the setup you described, but with a very strong gradient. I had a look for EM field effects on quarks and didn't find anything - anyone? But at this scale we need partical theory and the fields are mediated by photons.

    You must have done some electrostatics and magnetics in school by now surely?

    Classically - the electric fields act like the slopes of hills.
    Two opposing sets of + charges would make a long valley.
    The proton would be like a marble rolling along the valley.
  4. Jan 22, 2012 #3
    Thank you for responding.

    I somewhat understand now, but still I am curious on somethings. Do the N or S poles of a magnet attract a certain charges like does N attract a positive charge and south a negetive charge? In your 4th answer you said they dont split into many sub particles but rather into quarks, but it was my understanding that the collision of protons explodes into other particles such as positrons and what not.
    How about if the two magnets were "negetive"(I know you said magnets aren't + or -, but just go with me here), could the protons stay in the middle, or is there also a zero zone in an electromagnetic field as well?

    Anyway I appreciate the feedback. As to your question, no I have not studied any physics or anything like this yet,.. I am only in 10th grade earth science right now.
  5. Jan 22, 2012 #4
    No, the charges are not attracted to the magnetic poles.

    There's an exception though, and that's if the charge or magnets are moving relative to each other. Then, some of the magnetism transforms into electric field and some of the electric field transforms into magnetism. This is why they use strong magnets to make protons go around in a circle in particle accelerators.
  6. Jan 22, 2012 #5
    Antiphon, Thank you for your response.

    How exactly do they move relative to each other in the LHC?

    Maybe I should do some more research of my own, but I am trying to come up with a way to expose a protons quarks, without running it through the LHC. Anyway, thanks again.
  7. Jan 22, 2012 #6
    The protons spin around in the tube. The magnets are arranged around the tube and bolted down to the earth.

    If you could attach a little chair to the proton and ride with it, the magnets around the ring would look like they were spinning around you, and you would see large electric fields pulling on your proton. Those electric fields are the magnetic fields measured by the people who are operating the machine and not spinning with you on the proton.
  8. Jan 22, 2012 #7

    Simon Bridge

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    Just to add:
    You could have two regions of equal positive charge separated by a gap. If you "popped" a proton exactly in the middle between them, it experiences zero field and thus stays there.

    In fact, if it is a bit off to one side, it will get pushed back... and move back and forth across the center like a marble in a bowl.

    If you made the charged regions negative, then it would be more like trying to balance the marble on a knife-edge.

    Note: Antiphon is giving you relativistic descriptions - they are not too bad actually, but I was wondering if you may be better off with classical descriptions?

    In the classical description, a moving charge is an electric current. Electric currents generate a magnetic field. Magnetic fields interact with each other. So magnets won't attract charges, but they will affect electric currents.

    The kind of electric current most accessible to you is the kind you get in a wire - this is made of electrons but they'll do. You can experiment with a some magnets and a wire to see the effect.

    Youtube demos:
    Magnetic field around a wire:

    Magnetic field moving a wire when it has a current in it
    ... notice that the force is right-angles to the magnet poles?

    Probably the coolest thing you can do, easily, with electromagnetism at your grade-level is build a motor:
    ... also helps you get a feel for how these forces work.
    Last edited by a moderator: Sep 25, 2014
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