Why a magnetic monopole does not exist?
415417
Like a few other questions (why is the distribution of matter lumpy instead of smooth?), this can be answered if the inflationary theory of the Big Bang is correct. In this theory, the universe we have access to was once extremely tiny, and just by luck there weren't that many monopoles in it, maybe only a couple; so when it inflated to its present size, we end up with that very small number over the whole universe. \nOtherwise, it's an open question.
1097908
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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NO.......magnetic monopoles havent been discovered yet.\nSo magnetism is still in accordance with Maxwell's equation,\ndiv(B)=0
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Maxwell's equations require that in empty space the magnetic and electric fields are divergence free: Div B=0 , Div E=0. An equivalent way of saying that, is that for any closed surface, the integral of the normal (to the surface) component of the magnetic field over the surface is zero. For an electric field the integral of the normal component of the electric field over the surface gives the total net charge enclosed (zero in empty space).\n\nThere are other fields with this property as well. The word flux ("flow") probably comes by analogy with hydrodynamics. The velocity v(x) of an incompressible irrotational fluid (water for example) is an example of a divergence free field. Div v = 0 just means that the total amount of water flowing across any closed surface is always zero (unless the surface encloses a source) because for each element of water flowing in, an equal amount must flow out. \n\nAny field with this property can be represented visually by drawing continuous lines in space such that the direction of the lines gives the direction of the field, and the magnitude is proportional to the density of lines per unit area in a plane perpendicular to their direction. That is, electric and magnetic fields are identified as directional flux densities. The actual lines have no physical existence; they're a conceptual device.\n\nEach line starts at a source (positive charge) and terminate at a sink (negative charge), or else (especially in the case of a magnetic field) must form a closed loop. This makes it possible to visualize easily the structure of a field particularly when the geometry is simple. \n\nFor example it's obvious that a point charge produces a field in the radial direction which decreases as the square of the distance from the charge since the lines of flux must radiate outward from the charge.
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Why do magnets work? \nMagnetism is an invisible force felt within the space around a magnet.  This space, called the magnetic field, can either attract (pull) or repel (push away) other magnets and some types of metal.\n\nAll magnets have two ends (poles).  These poles are opposites and are called the north and south poles.  Opposite poles attract, while like (similar) poles, repel.\n\nThe Earth’s core has its own magnetic field.  Magnetic north and south are near the geographic north and south poles.\n\nNASA has been experimenting with magnetic fluids for over 30 years. Magnetic fluids were made to help put fuel into a rocket engine. NASA was trying to solve the problem. of how to move fuel without gravity.  Tiny pieces of iron were put into the fuel. A magnet pulls the iron and could help get the fuel into the engine.\n\nMagnetic fluids are made by mixing pieces of metal in liquids to make a fluid that is very different from other liquids. It will stick to a magnet and can be directed by magnetic forces. Magnetic fields can shape the fluid, and magnetic fluids can change their thickness. They become hard around magnets.\n\nScientists have tried to use magnetic fluids to solve other problems. They’re used to make better computers. Scientists are still thinking of new ways to use the fluids.\n\nYou may use magnetic fluids!  Some cars have them in their shock absorbers. They are used in some buildings and bridges. The fluids help protect structures from damage from earthquakes or strong winds. There is still a lot to learn about these magnetic fluids. NASA is using the Space Station to learn more about them. They hope to find new ways to use them. \n\nKSNN thanks NASAexplores as a source of information. For more information about this topic and additional teaching resources go to http://www.nasaexplores.com
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The attractive force of the "magnet earth" is much smaller than it's gravitational force. In fact it's negligibly small. Proof: put an iron object on the table, like a knife. Despite it being much more closer to the earth than the moon, it will not budge.
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Gee .. been a while.  If I remember correctly the magnetic field is perpendicular to the electrical field.  Thus around the two wires the magnetic fields move in the same direction and combine, producing a net attractive force.\n\nIf the currents go the opposite direction, the forces repel.\n\nSee the link below for a more detailed explanation and pictures:
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By using particle collisions, it is possible to show that there is *something* inside of protons, for example. These 'somethings' have the properties that the theorists predict that quarks will have. Furthermore, the theoretical predictions made by the quark models (such as decay rates, reaction cross sections, etc) are in agreement with what is actually seen in the accelerators. This is why we say that quarks exist even though nobody has seen an isolated quark (and there are good theoretical reasons why we may never see one).\n\nOn the other hand, the strings in string theory are *incredibly* small, which means we need very high energies to probe them. No particle accelerator that we have right now will produce these energies. Also, the strings are what would describe the nature of the quarks, not show they don't exist. The question is whether they are point particles or extended to some (small!) degree.
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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.
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Einstein alluded about forces saying that they are fictitious.This make sense because forces do not exist unless there is an interaction between two entities.\nThe magnetudes of interaction depends on the densities of the masses and their volume.The greater the densities the greater the interaction.Thus we can categorize them.\nHowever ;the mechanisms involved is the same in all interactions!Einstein Related this mechanism to a curvature.\nHe had discovered when a force comes into being it comes  from a common  mechanism(.A force is a force ). Force only come into being only as pairs.A force cannot exist by itself no more than a magnet having a single pole.\nUnfortunately ,He had the basis for a Unified Theory and did not realize it.\nAs far what has been measured in the interaction of micromasses or micromasses,I  dont believe there is anything exact.Only approximtions.\nThe phenomena of gravity apply to both micromasses as well as Macromasses.This is the only thing that is Realistic.\nIn other words Electrical phenomena as well Gavity are all one and the same Phenomena.\nYou may not agree with it but its a more realistic answer than resorting to the aphabetic soup of forces that the Physists have concocted as saying that they are different Phenomenae.\nIf you dont understand about their description of weak,strong nuclear forces, dont feel bad. I doubt that they fully understand it themselves!
155611
You may be misusing a term.  Magnetostatics is a study of static magnetic fields.  In other words, where the current producing the magnetic field does not vary with respect to time.\n\nIf you are talking about monopole magnets, then this is impossible, based on maxwell's equations, the divergence of B is 0.  All magnetic fields are in closed loops.
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I had the same problem when I learned about both of them. \nBut now think of it in a different way. You are assuming that the magnetic FORCE that magnets have on certain metals. But if you think about it carefully they don't create or destroy energy. \nIf you don't beleive me consider a piece of iron with only gravity working on. But its height is 0 so it has no Potential or Kinetic energy. But now let's say you bring in a magnet. Now naturally that will make the iron bar rise and stick to the magnet. Now a natural assumption would be that you just created potential energy because the height of the iron bar just increased. But now you have to consider the fact that magnet is still putting some force on the Iron bar. So no change in potential energy occured. No change in Kinetic energy occured once the bar stuck to it. and the Energy needed to bring the bar up could be accounted by the energy needed to bring iron bar in. This shows that there was no energy created.  \nI think that you are trying to overthink the problem. I think this should help good luck.
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The most interesting fact I know?  That they don't exist and that they're some stupid idea somebody came up with to help explain a few things we don't currently understand.  Singularities have infinitely dense mass?  Riiiight.\n\nYou'd better start reading up on the Electric Universe, buddy.  There are powerful magnetic fields all over the Universe, and the stupid idiot "scientists" running the show right now don't like to acknowledge that maybe there are electric currents shaping our galaxies.
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We can shape magnetic fields to trap things, but those things must be moving charged particles.\n\nHumans are not magnetic and even a very strong magnetic field will not restrain them at all.
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Magnetic forces, electric forces are bi-polar: there are North and South poles on magnets, as well as positive and negative charges. As a result the forces can be attractive or repulsive.\n\nGravity is mono-polar in the sense that the force between two masses is always attractive.
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Actually, a light beam is invisible as well, unless it's shined directly into our eyes.  A light beam is visible in a dusty room, and a magnetic field is also visible when loose iron filings are present.  The reason why magnetic fields seem invisible to us is merely because our eyes aren't tuned to pick up magnetic fields, but that does not say that it's impossible to devise an artificial eye that can "see" such magnetic fields.
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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.