Which particle is responsible for a material's magnetic properties?
157065
1. mico-elcetric currents are responsible for an elt's magnetic props...\n\n2. electron motion or spin in atoms
31282
magnet \n\nAn object that attracts iron and some other materials. Magnets are said to generate a magnetic field around themselves. Every magnet has two poles, called the north and south poles. Magnetic poles exert forces on each other in such a way that like poles repel and unlike poles attract each other. A compass is a small magnet that is affected by the magnetic field of the Earth in such a way that it points to a magnetic pole of the Earth. (See magnetic field and magnetism.)
31611
Well even though humans have known about magnets for thousands of years, the real reason they work is still somewhat mysterious. Depending on how deep you want to investigate, it can be a very complicated phenomenon. \n\nA magnet is, at its foundation, caused by the movement of electrical charge (yes this is the Biot-Savart Law). When charges (like electrons for example) move, they produce magnetic fields. If a charge moves in a loop, it creates a magnetic field. The magnetic field can be basically represented by an invisible set of arrows in space, that point in a direction. In the case of the loop, the arrows of the magnetic field will point out of the loop for a positive charge moving counter clockwise (this is the so-called "right hand rule"), and into the loop for a charge moving clockwise (some pictures are in the reference attached). \n\nThe magnetic field has a "north" end and a "south end". The little arrows from our moving charge are pointing in the "north" magnetic direction, and away from the "south" magnetic direction. It is a mysterious and interesting property of electromagnetism that two objects with fields that oppose each other, i.e., the little arrows of the field do not line up, so either the north end of one field is facing the north end of the other field, or the two south ends are facing each other, repel, or resist movement of the two objects towards each other with some force. \n\nOn the other hand, if the little arrows line up, the two objects attract each other with some force. \n\nThe forces that result from magnetic fields (and for that matter, electric fields) are fundamental forces, and part of the four fundamental forces of the universe (strong, weak, electromagnetic and gravity).  It is believed that these forces are caused, at their base, by particles passing "messenger particles" back and forth. In the case of electromagnetism, the messenger particle is a photon. How this actually works is still somewhat poorly understood, and is involved with the world of quantum mechanics, which is very counterintuitive but interesting. \n\nHowever, what is important is that we understand it well enough to make models of magnetism, and to make predictions based on those models which we can verify and use. All of electricity and electric motors are based on our ability to design systems with magnets and to be able to build and use them.
209289
start here:\nhttp://en.wikipedia.org/wiki/Magnet
309230
Magnetism is actually a relativistic effect caused by moving charge. Current travelling in a wire has a magnetic field surrounding it. Bar magnets are special in that all the magnetic moments (the magnetic effect of electrons orbiting their nucleii) are aligned. In most materials the moments are randomly aligned and cancel each other out.
927615
Actually paper does interact with magnetic fields.  It "hinders" the magnetic field.  I am referring to the ease with which the magnetic flux can pass through a substance.  Everything has a such a value.  It is comparable to the dielectric constant in capacitors.  Metals pass magnetic fields fairly readily though there is some difference even between the metals.
50619
well, a couple i can think of:\n\n- NMR (which, from looking at your gyromagnetic ratio question, i suspect is your thing, so i wont explain it)\n- hyperfine structure of spectral lines (comes from the coupling of nuclear to electronic spins)\n- you can also stick 'em in the path of a highly accelerated particle beam and measure the scattering as a function of azimuthal angle.  when i worked at SLAC we ran an experiment that did just this.\n\nthat's all i can come up with off the top of my head!
662574
It might be due to the number of unpaired electrons which causes a large amount of net magnetic moment making the material more magnetic.  This is the property of a ferro magnetic material.
30487
Well even though humans have known about magnets for thousands of years, the real reason they work is still somewhat mysterious. Depending on how deep you want to investigate, it can be a very complicated phenomenon. \n\nA magnet is, at its foundation, caused by the movement of electrical charge (yes this is the Biot-Savart Law). When charges (like electrons for example) move, they produce magnetic fields. If a charge moves in a loop, it creates a magnetic field. The magnetic field can be basically represented by an invisible set of arrows in space, that point in a direction. In the case of the loop, the arrows of the magnetic field will point out of the loop for a positive charge moving counter clockwise (this is the so-called "right hand rule"), and into the loop for a charge moving clockwise (some pictures are in the reference attached). \n\nThe magnetic field has a "north" end and a "south end". The little arrows from our moving charge are pointing in the "north" magnetic direction, and away from the "south" magnetic direction. It is a mysterious and interesting property of electromagnetism that two objects with fields that oppose each other, i.e., the little arrows of the field do not line up, so either the north end of one field is facing the north end of the other field, or the two south ends are facing each other, repel, or resist movement of the two objects towards each other with some force. \n\nOn the other hand, if the little arrows line up, the two objects attract each other with some force. \n\nThe little arrows are aligned along the so-called "magnetic lines of force". \n\nThe forces that result from magnetic fields (and for that matter, electric fields) are fundamental forces, and part of the four fundamental forces of the universe (strong, weak, electromagnetic and gravity). It is believed that these forces are caused, at their base, by particles passing "messenger particles" back and forth. In the case of electromagnetism, the messenger particle is a photon. How this actually works is still somewhat poorly understood, and is involved with the world of quantum mechanics, which is very counterintuitive but interesting. \n\nHowever, what is important is that we understand it well enough to make models of magnetism, and to make predictions based on those models which we can verify and use. All of electricity and electric motors are based on our ability to design systems with magnets and to be able to build and use them.
139636
Electromagnets are made out of metal that can easily be magnetized by applying DC voltage. Electromagnets do not occur naturally in nature but are manmade. Their magnetism can be turned on and off.\n\nPermanent magnets occur naturally in nature.
89147
>>Theory of magnetocrystalline anisotropy\n\nThe direction of a magnetization relative to body that supports it is determined mainly by two effects, shape anisotropy and magnetocrystalline anisotropy. The first arises from magnetostatic effects and the second from spin-orbit coupling between the spins and the lattice of the material. The magnetostatic effects can be calculated from micromagnetic calculations, but the magnetocrystalline anisotropy must be computed from the electronic structure of the material. This is an important quantity because it determines whether a magnetic material can be made into a good hard magnet, a good soft magnet or neither. Hard magnets are an essential component of electromagnetic motors and soft magnets are an essential component of transformers.<<\n\nThe rest of that quote can be found in the source link:
564016
A magnet consists of molecular magnets.\nIf these magnets are arranged uniformly then the magnet will be stronger.\nIn an ordinary piece of iron there are molecular magnets, but since they are irregularly arranged there is no net magnetic field created.
1161988
No.\n\nBut it can when it is heated.\n\nIf you heat a magnetic material above its Curie temperature, it depolarises and stops being magnetic.
213584
A magnetic field is produced by moving electric charge (electric current). The strength of the field depends on the size of the current.\nBigger current -> Bigger magnetic field, i.e stronger magnet.\n\nIn "permanent magnets" the "current" is a result of atoms aligning theselves (their spins actually) in the same way, such that electrons "orbiting" the atoms (spin) result in a virtual current loop around the outside of the magnetic material. Inside the material their is no such virtual current since the current from one atom is cancelled by current in the opposite direction from a neighbouring atom, but at the outside of the material there is no neighbouring atom to balance the current. The more atoms that are in alignment the greater this virtual current and the greater the strength of the magnet. There is a theoretical maximum magnet strength for a given peice of material: that strenth when the spins of all the atoms are aligned.\n\nVisualizing a box full of spinning tops might aid understanding. Furthermore imagine what would happen if you could wrap a string around the group of tops. Imagine the string is effected by the tops motions, but the tops motions are not affected by the strings motion.
451560
A magnet is an object that has a magnetic field. The word magnet comes from the Greek (magnētēs lithos), which means "magnesian stone". Magnesia was an area in Ancient Greece, in present-day Manisa, Turkey where deposits of magnetite have been discovered since antiquity.\n\nElectronic generation of magnetism\nElectrons play the primary role in generating a magnetic field. Within an atom, electrons can exist either individually or in pairs within any given orbital. When they are paired, the individuals in that pair always have opposite spin — one up, one down. The fact that the spins have opposite orientation means that the two cancel one another. If all electrons are paired, no net magnetic field will be generated.\n\nIn some atoms, there are electrons that are unpaired. All magnets have unpaired electrons, but not all atoms with unpaired electrons are ferromagnetic. In order for the material to become ferromagnetic, not only must there be unpaired electrons present, but those unpaired electrons must interact with one another over long ranges such that they are all oriented in the same way. The specific electron configuration of the atoms (as well as the distance between atoms) is what leads to this long range ordering. The electrons find that they can exist in a lower energy state if they all have the same orientation.\n\n\nNorth-south pole designation and the Earth's magnetic field\nA standard naming system for the poles of magnets is important. Historically, the terms north and south reflect awareness of the relationship between magnets and the earth's magnetic field. A freely suspended magnet will eventually orient itself north-to-south, because of its attraction to the north and south magnetic poles of the earth. The end of a magnet that points toward the Earth's geographic North Pole is labeled as the north pole of the magnet; correspondingly, the end that points south is the south pole of the magnet.\n\nThe Earth's current geographic north is thus actually its magnetic south. Confounding the situation further, magnetised rocks on the ocean floor show that the Earth's magnetic field has reversed itself in the past, so this system of naming is likely to be backward at some time in the future.\n\nFortunately, by using an electromagnet and the right hand rule, the orientation of the field of a magnet can be defined without reference to the Earth's geomagnetic field.\n\nTo avoid the confusion between geographic and magnetic north and south poles, the terms positive and negative are sometimes used for the poles of a magnet. The positive pole is that which seeks geographical north.\n\n\nCommon uses for magnets\nMagnetic recording media: Common VHS tapes contain a reel of magnetic tape. The information that makes up the video and sound is encoded on the magnetic coating on the tape. This is why magnets will destroy the information in these types of tapes. Common audio cassettes also rely on magnetic tape. Similarly, in computers, floppy disks and hard disks record data on a thin magnetic coating. \nCredit, debit, and ATM cards: All of these cards have a magnetic strip on one of their sides. This strip contains the necessary information to contact an individuals financial institution and connect with their account(s). \nCommon televisions and computer monitors: The vast majority of TV's and computer screens rely in part on an electromagnet to generate an image--see the article on cathode ray tubes for more information. Plasma screens and LCDs rely on different technology entirely. \nLoudspeakers and microphones: Loudspeakers actually rely on a combination of a permanent magnet and an electromagnet. A speaker is fundamentally a device to convert electric energy (the signal) into mechanical energy (the sound). The electromagnet carries the signal, which generates a changing magnetic field that pushes and pulls on the field generated by the permanent magnet. This pushing and pulling moves t
512643
ferromagnet materials will lose their magnetism if heated above a point known as the Curie temperature. \nExposure to an opposing magnetic field will "knock it down", but not demagnetize it completely.
989535
The exchange of electrons between atoms, making atoms have a charge, which creates magnetism. Depending on the direction of the spin of the electrons around the nucleus, if an unequal amount of electrons spin in two different directions, there will be magnetism. \n\nMagnetism is also created by running an electric current through a particular substance, electromagnetism.\n\nAll materials have magnetism, but most are in a very minute amount.