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Physics/The magnetic field of electric currents


Permanent magnet, copper wire and soft iron
Permanent magnet, copp  

I have been reading about the magnetic field of an electric current, and I was wondering if you could help me understand what would happen in a situation where a permanent magnet was connected to a copper wire, and the opposite end of the wire was connected to a piece of soft iron. How would an electric current running through the copper wire effect the magnetic field of the permanent magnet?
I have noticed that a magnet touching a nail will magnetize the nail so that it will also attract a second nail. Is it possible that a current through the copper wire could ever have the same effect?  
I have looked this up, but cannot seem to find any answer. Can the B field of a permanent magnet magnetize a ferrous metal object nearby when the two things are linked by a current-carrying copper wire? What kind of factors would determine whether this would happen? The strength of the permanent magnet? The strength of the current? The direction the current flows? The length of the copper wire?

As you have no doubt realized by now, I really know very little about science....

But I am trying to learn.
Thank you kindly,

No, the scenario you drew up there will not magnetize your iron chunk at all.  Magnetic fields magnetize ferrous materials, not electric currents.  Electric currents can create magnetic fields, but in the configuration you drew it you'd pretty much get zero magnetic field at the piece of iron in the picture.  And the current in no way connects the permanent magnet to the iron chunk.


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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