What makes an ordinary bar magnet magnetic select al answers

What makes an ordinary bar magnet magnetic? (select al answers that apply) electrons inside it are themselves tiny magnets the magnetic fields of electrons in the magnet are aligned, and add together it contains magnetic charges none of the above

Solution

answer is(a) and (b)

As you probably know, any flowing charge - current that is - whose path makes a \"loop\" will act like a coil of an electromagnet and generate a magnetic field \"through\" the loop. Picture a hydrogen atom - the simplest case. Following the electron through one orbit (and not getting caught up in the effects of the uncertainty principle and other quantum aspects) we have a charge moving in a loop. Therefore, for that moment of that orbit, we have a little magnet that can be acted upon by the magnet , and influence all the future orbits to not be quite so random and continue interacting with the external magnetic field.
This will tend to ALIGN the atom with the field of your magnet -- I have already oversimplified so many details to get to this point that I just can\'t say that it attracts the other atom.
In the real world, when I bring an external magnetic field near an object, there will be some electrons in some of the atoms at that moment that happen to be orbiting in a favorable way to interact with the magnetic field like the atom in the above example. The field will tend to keep the orbit in that orientation, and that may boost the local magnetic field to now aaffect other nearby orbiting electrons and this may continue until there is a net orientation to the electron orbits in the atoms of the material and the entir object behaves like a magnet.
If this object was predisposed to behave like a magnet - like a material with iron in it, then this adjustment to the random alignment can be accomplished with a relatively waek external magnetic field. If the object is not at all magnet-like, like a frog for instance, then the external magnetic field must be super-duper strong. But sooner or later, all natural materials will exhibit magnetism in ths way if you can apply a srtong enough external magnetic field.