# What is magnetic force and how does it work?

There are a lot of people out there that find magnetism fascinating but have no clue what it is and how it really works and I'm one of them!

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7 years ago
I don't know if the nature of magnetism is something that can be explained in just a few paragraphs.  The explanation requires that you believe in some other imaginary things like electric charge, electric current, electric fields, and magnetic fields.  Usually the whole story takes about a semester to tell, and its called "electricity and magnetism", and this story is one chapter in a story called "physics".

For example at MIT, they call this class, "Physics 2: Electricity and Magnetism"  Here:
http://ocw.mit.edu/courses/physics/

This site linked above appears to be giving away notes, and video lectures on this class, and others, like, for free, if you've got the time and/or the attention span for it.

If you'd prefer that someone just tell you what the story is with magnetism, in as few sentences as possible, the best summary I can come up with is this:

Magnetic fields are created by electric currents, that is moving electric charges.  For example, you can create a magnetic field in the laboratory, by driving electric current through a coil of wire.

Permanent magnets are somewhat more mysterious.  Again the magnetic field of a permanent magnet is due to electric currents, moving charges, but in the case of a permanent magnet these currents are microscopic.  Moreover these microscopic currents can somehow keep "running" without generating heat the way currents in copper wires lose power to heat.  Or another way to say this is:  if permanent magnets are losing energy to self-heating, they do so very, very, slowly.

The actual forces that result when magnetic fields interact with, other magnetic fields, electric currents, moving charges, etc... these forces are best described mathematically.
http://en.wikipedia.org/wiki/Force
http://en.wikipedia.org/wiki/Lorentz_force_law
http://en.wikipedia.org/wiki/File:Cyclotron_motion.jpg

kcls7 years ago