what is magnetism exactly?
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Magnetism is the property of magnetic materials to exert forces of certain objects, mainly iron and other magnetic materials; this force is known as the magnetic force.\n\nThe origin of this force is the movement of electrons or charged particles (ions) inside the materials.  When an electron spins around the atom's nucleus, according to the Biot-Savart Law it produces what we call a Magnetic Field, which exerts Magnetic Induction on it's surroundings.  Not only that, but also moving electrons in the surroundings of the original one (say, electrons of another object) will "feel" this induction as a force.\n\nSo, everything exerts a magnetic force on everything else, but the thing is that the magnetic induction and hence the direction of the force electrons in the surroundings will feel depend on the direction in which the original electron is moving (more specifically, on the vector Angular Momentum and/or the vector Magnetic Moment), and since there are lots of electrons moving in different directions in every material, the forces will point in every direction, cancelling themselves and producing a net force equal to zero.\n\nBut magnetic materials have the property of "aligning" the Angular Momentum/Magnetic Moments of all its atoms, and the forces produced by all its electrons (in the average) point in the same direction, producing the net force we feel when we put a magnet (magnetic material) near some piece of iron (a material susceptible to magnetism).\n\nHope I helped
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Gold and silver are not ferromagnetic materials and so do not have any magnetic properties. \n\nThe following explanation is from school for science.com  \n\n"Ferromagnetic materials are strongly attracted by a magnetic force. The elements iron (Fe), nickel (Ni), cobalt (Co) and gadolinium (Gd) are such materials. \n\nThe reasons these metals are strongly attracted are because their individual atoms have a slightly higher degree of magnetism due to their configuration of electrons, their atoms readily line up in the same magnetic direction, and the magnetic domains or groups of atoms line up more readily. \n\nIron and steel\nIron is the most common element associated with being attracted to to a magnet. Steel is also a ferromagnetic material. It is an alloy or combination of iron and several other metals, giving it greater hardness than iron, as well as other specialized properties. Because of its hardness, steel retains magnetism longer than iron.\n\nPermanent magnets\nAlloys of iron, nickel, cobalt, gadolinium and certain ceramic materials can become "permanent" magnets, such that they retain their magnetism for a long time."\n\nTry looking at the website for more information. Hope that helps!
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Diamagnetism is a form of magnetism which is only exhibited by a substance in the presence of an externally applied magnetic field.\n\nParamagnetism is the tendency of the atomic magnetic dipoles to align with an external magnetic field. This effect occurs due to quantum-mechanical spin as well as electron orbital angular momentum.  \n\nParamagnetism requires that the atoms individually have permanent dipole moments even without an applied field.\n\nArsenic is not a paramagnetic substance.
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Electromagnetic is a term that refers to electric and magnetic fields.  Since they are actually one and the same thing, they are collectively called electromagnetic.
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Magnetism arises from the movement of electric charge. It is a manifestation of the electrosatic force (there is per se no magentic force). \n\nA moving charge always creates and polarised magnetic field - ie it has a north and south. Monopoles do not exist.\n\nHowever, it would be equally possible to describe the situation with magnetic monpoles leading to polarised electric charge. \n\nNo magenticm monopoles have been found to exist.
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Electro-magnets use electricity to temporarily align all of the atoms in a ferrous material to a N-S position. When the electricity is turned off, the atoms return to their original misaligned state, losing much of its magnetivity. It never completely loses all of it, as some atoms will remain in the alligned state, creating a "Gauss" feild around it.
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Conduction?  I'm not aware of magnets having such a property.
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No, there is no relation between angular momentum and magnetism- The "spin" of the electrons isnt a spin in the sense of moving in a circular direction, but just a convenient term to describe an essentially quantum quality of the electron-Similar to calling subatomic particles by Charm and Up...they dont describe the characteristic one would associate with macroscopic objects.  There is no sense of "motion" associated with electron spin.  At any rate, the electron is so infinitesemally (sp?) light compared to the atomic nucleus that even if it were moving, it wouldn't impart significant momentum to the object as a whole-even if it were a large fraction of the electrons.
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It's just like "positive and negative" for magnetism, isn't it?  People say them as though they mean something.  All they really mean is that there are two types of magnetic things--like ones repel, opposite ones attract.  We don't know why it's so, but we feel much better when we can attach a word to it.\n\nWe understand many things about gravity (as we do about magnetism), but we can't explain why it exists in the first place.  That question is not even in the scope of physics, really, because it can't possibly be confirmed or denied by any experiment.  But like many things, we want to believe that we understand it.
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regular magnets are natraly magnitised, they maintain their magnetic properties with out aid of an outside force\nelectro magnets use a coil of wire, with a curent passing through it, wraped around a piece of metal to create the magnitism. when you remove the curent, it loses its magnetism.
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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.
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regular magnet is a permanent one and electromagnet is an artificially created magnet which behaves as a magnet when current is passed through a wire around a iron bar\nelectromagnets are widely used
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Paramagnetism is a form of magnetism which only occurs in the presence of an externally applied magnetic field. Paramagnetic materials are attracted to magnetic fields, hence have a relative magnetic permeability greater than unity (or, equivalently, a positive magnetic susceptibility). However, unlike ferromagnets which are also attracted to magnetic fields, paramagnets do not retain any magnetisation in the absence of an externally applied magnetic field.\n\nDiamagnetism is a form of magnetism that is only exhibited by a substance in the presence of an externally applied magnetic field. It is the result of changes in the orbital motion of electrons. Applying a magnetic field creates a magnetic force on a moving electron in the form of F = qv × B. This force changes the centripetal force on the electron, causing it to either speed up or slow down in its orbital motion. This changed electron speed modifies the magnetic moment of the orbital in a direction opposing the external field.
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Log on to http://en.wikipedia.org/wiki/Magnet\n\nand check out Characteristics of magnetic materials
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Hysteresis is the slight difference between how something reacts going one way compared to how it acts going the other way.\n\nA typical example is a magnet. As it magnetizes, it passes through the origin (the point at which 0 electric field intensity equals 0 magnetic field intensity). This is because the initial charge of magnetism is going into an "empty" container, so to speak.\n\nHowever, when the magnet is demagnetized (or the field is flipped to the opposite polarity), there will be a small amount of "residual" magnetism from the first charging that will tend to "fight" against the reversal. What this really means is that the reverse polarity charge does not follow the exact same path ... and does not pass through the initial origin at all.\n\nYou could look at this as filling and then emptying a glass with water - the first time you fill it, the glass started out completely dry ... which meant you could put X many molecules of water into it. Then you dump it out ... but a few molecules remain adhered to the glass surface (this would be the residual). The next time it's filled, you add as much as the first time (less the residual).\n\nWhen you empty it again, it leaves a couple of molecules attached. Not necessarily the same ones as the first time, but approximately the same amount. Hence there is now a hysteresis effect occurring when you fill/empty the glass.
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Iron, cobalt and nickel can be magnetic. They can be made to have polarity. Poles that are alike repel and poles which are not alike attract. A magnet will attract all of them if they are not polarized. If they are polarized, a magnet will attract or repel according to the polarity.\n;-D
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Magnetization of materials\n\nFerromagnetic materials can be magnetized in the following ways:\n\n* Placing the item in an external magnetic field will result in the item retaining some of the magnetism on removal. Vibration has been shown to increase the effect. Ferrous materials aligned with the earth's magnetic field and which are subject to vibration (e.g. frame of a conveyor) have been shown to acquire significant residual magnetism.\n    \n* Placing the item in a solenoid with a direct current passing through it.\n    \n* Stroking - An existing magnet is moved from one end of the item to the other repeatedly in the same direction.\n    \n* Placing a steel bar in a magnetic field, then heating it to a high temperature and then finally hammering it as it cools. This can be done by laying the magnet in a North-South direction in the Earth's magnetic field. In this case, the magnet is not very strong but the effect is permanent.\nMagnetization of materials\n\nFerromagnetic materials can be magnetized in the following ways:\n\n* Placing the item in an external magnetic field will result in the item retaining some of the magnetism on removal. Vibration has been shown to increase the effect. Ferrous materials aligned with the earth's magnetic field and which are subject to vibration (e.g. frame of a conveyor) have been shown to acquire significant residual magnetism.\n    \n* Placing the item in a solenoid with a direct current passing through it.\n    \n* Stroking - An existing magnet is moved from one end of the item to the other repeatedly in the same direction.\n    \n* Placing a steel bar in a magnetic field, then heating it to a high temperature and then finally hammering it as it cools. This can be done by laying the magnet in a North-South direction in the Earth's magnetic field. In this case, the magnet is not very strong but the effect is permanent.