Why is magnet in earth not destroyied due to heat?
107873
Because the magnet is just Iron, which can be heated up a LOT without disintergrating.  In fact, the pressure keeps it as a solid, which wouldn't normally happen at that temperature.
856254
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.
920912
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.
669781
Magnetic property of a material is due to the arrangement of Domains in it. If you are not of science background, simply think it as it is the arrangement of atoms of the material, which is responsible for its magnetism. If you provide a permanent magnet with electric supply, the arrangement of atoms in it will be disturbed resulting in loss or decrease in its magnetism.\nNot only the electric supply, but heating or even strong jerks can also lead to the disturbed atomic arrangement and therefore decreased or completely lost magnetism.
827354
The magnetic field of Earth is caused by molten iron rotating around in the core.  The lines of magnetic flux follow the right-hand rule (RHR).  Curve the fingers of your right hand into a loose fist and extend your thumb upward.\n\nAs the molten iron swirls around in the direction of your curled fingers, the flux is emitted in the direction of your extended thumb.  The flux is created because the swirling molten iron creates an electrical current that follows the swirl.  That current, like a current going through a coil, creates the magnetic flux.\n\nA flux is simply a line of force and that force, like all forces, has direction.  In this case, the force points outward in the direction of your thumb.  That's called the magnetic north pole, by convention.  \n\nHowever, because the magnetic flux exits the Earth at this pole it really is the south pole.  This can be verified because the north pole of a compass needle will point north and, as you well know, north is attracted to south.  Thus, the magnetic north pole is really the south pole...argh...physics is so complicated.\n\nAs to why like poles repel and dissimilar poles attract, blame in on the direction of the forces...the flux of that magnetic current.  (Magnetism does not really flow, but the forces act as though it does.)  Two similar poles either push each other away (e.g., two south poles) or pull away from each other (e.g., two north poles) because the forces are toward or away from the two magnets respectively.  Two dissimilar poles attract each other because the alligned forces pull one toward the other when they are all in the same direction.  [See source.]
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.
631866
In a way this true in part, as most of the more volatile substances such as gases, liquids, and less dense minerals have already been scorched away leaving primarily denser rock. Thus, it has essentially no atmosphere save a trace of hydrogen (possibly owing to its proximity to the sun) and is very dense with a heavy iron core reaching very close to the surface. It rotates slowly like meat roasting over a fire with a day lasting two of its 88 Earth-day revolutions around the sun. The temperatures are indeed extreme, varying from 800 degrees during the 3 month long day to -300 degrees at night. All of this means that it has managed to reach a state of relative stability over the last 4 billion years or so and will likely continue for some time to come.
27845
Magnetism is caused by  electrical charges in motion. This is not necessarily something unique to electrical equipment, which is the case for electromagnetism, but also for permanent magnets. It is the motion of the electrons around the nuclei, and also the spin of the electrons, that cause the magnetism in a natural magnet. The magnetic field of Earth is believed to come from movements inside the planet, where oceans and rivers of melted metals exist.\n\nI can only think of two types of magnet; natural magnet and electro-magnet.
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.
108424
Earth's magnetic field (and the surface magnetic field) is approximately a magnetic dipole, with one pole near the geographic north pole and the other near the geographic south pole. An imaginary line joining the magnetic poles would be inclined by approximately 11.3° from the planet's axis of rotation. The cause of the field is probably explained by dynamo theory. The magnetic field extends several tens of thousands of kilometres into space as the magnetosphere\n\nThe locations of the magnetic poles are not static but wander as much as 15km every year (Dr. David P. Stern, emeritus Goddard Space Flight Center, NASA). The two poles wander independently of each other and are not at directly opposite positions on the globe. Currently the south magnetic pole is farther from the geographic south pole than the north magnetic pole is from the north geographic pole.\n\nThe field is similar to that of a bar magnet, but this similarity is superficial. The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons (negatively charged particles) within iron atoms. The Earth's core, however, is hotter than 1043 K, the Curie point temperature at which the orientations of electron orbits within iron become randomized. Such randomization tends to cause the substance to lose its magnetic field. Therefore the Earth's magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.\n\nAnother feature that distinguishes the Earth magnetically from a bar magnet is its magnetosphere. At large distances from the planet, this dominates the surface magnetic field.\n\nElectric currents induced in the ionosphere also generate magnetic fields. Such a field is always generated near where the atmosphere is closest to the Sun, causing daily alterations which can deflect surface magnetic fields by as much as one degree.\n\nMagnetic field variations\n \nGeomagnetic variations since last reversal.The strength of the field at the Earth's surface ranges from less than 30 microteslas (0.3 gauss) in an area including most of South America and South Africa to over 60 microteslas (0.6 gauss) around the magnetic poles in northern Canada and south of Australia, and in part of Siberia.\n\nMagnetometers detect minute deviations in the Earth's magnetic field caused by iron artefacts, kilns, some types of stone structures, and even ditches and middens in geophysical survey. Using the magnetic instruments adapted from airborne devices developed during World War II to detect submarines, the magnetic variations across the ocean floor have been mapped. The basalt -- the iron-rich, volcanic rock making up the ocean floor -- contains a strongly magnetic mineral (magnetite) and can locally distort compass readings. The distortion was recognized by Icelandic mariners as early as the late 18th century. More important, because the presence of magnetite gives the basalt measurable magnetic properties, these magnetic variations have provided another means to study the deep ocean floor. When newly formed rock cools, such magnetic materials record the Earth's magnetic field.\n\nIn October 2003, the Earth's magnetosphere was hit by a solar flare causing a brief but intense geomagnetic storm, provoking unusual displays of aurorae.\n\nMagnetic field reversals\n\n\n\nMain article: geomagnetic reversal \nBased upon the study of lava formations in Hawaii, it has been deduced that the Earth's magnetic field reverses at intervals, ranging from tens of thousands to many millions of years, with an average interval of approximately 250,000 years. The last such event, called the Brunhes-Matuyama reversal, occurred some 780,000 years ago.\n\nThe mechanism responsible for geomagnetic reversals is not well understood. Some scientists have produced models for the core of the Earth wherein the magnetic field is only quasi-stable and the poles can spontan
1150478
It's widely believed in the scientific community that the earth has a liquid mantle (that's where magma/lava comes from) and a solid super-hot iron core.  Good luck digging through that.
886336
Different metals have different magnetic field strengths.\n\nFor example, neodymium magnets are among the strongest.
1173935
Magnetic field has to do with the polarize charge of material, such as Iron.  \n\nIt is believed there is significant Iron near the center of the earth and yes rotation will cause the charges to align and thus create a magnetic field.  This is called the "Dynamo Theory".\n\nJUST BEING IRON DOES NOT MAKE THINGS MAGNETIC.\n\n"Previous theorists have assumed that the entire Core (or the Inner and/or Outer Core) rotates as a single flowing object within the Earth. If that were the case, then all of the charged (ionized) Iron material  would follow a relatively circular path around a single axis that we could call the Magnetic Axis. Basic Physics tells us that when electrical charges follow a closed (relatively) circular path (which is effectively a current), a magnetic field is always created as a result. The measurable evidence of this scenario would be a simple "dipole" magnetic field, with a single North Pole and a single South Pole, geographically exactly opposite each other on the surface of the Earth."\n\nSo if this theory where correct the Earth stopping it's rotation would in allow the magnetic field to fad.  But there are major problems with the theory.  For example it is known that the magnetic poles have flipped (Switched places) several time in Earths past.  Will if we have magnetic poles because of the earth's rotation to switch poles we'd need to reverse the cores rotation.  This would be an ungodly amount of energy.  There is nothing known that would do this once let alone a number of times.  And even if something could do it, we should have seen signs of the massive damage that would have resulted with these forces in play, like the Earth falling apart.   But in fact the poles shifting seems to be a pretty peaceful process on a planetary scale. \n\nAnd that is only one problem with the theory.  This is actually a very, very complex subject and there really is no way to know what effect the Earth stopping would have on the magnetic fields.  But I have attached a link to a very good article on the subject and it's pretty easy reading (Keeps the scientific jargon down and uses layman terms.)\n\nOthers are correct tough in what holds us to the Earth is gravity, not magnetics.  So it's the Mass (How big and dense it is) that keeps us here.  And rotation actually wants to make thing's fly away from it.  So we stay because the Earths gravity overcomes the acceleration.  So the acceleration of 1000mph is actually always enacting upon us, making us want to fly off the planet.  So stopping the Earth will not make us fly off as others have posted.\n\nThink of the spinning rids at the fairs and theme parks.  When you spin you are thrown away from the axis, the best example is the cylinder you go in and stand up against the wall.  When it spins your back is pushed against the wall, even as it turns so you are now spinning vertically like a tired, instead of horizontal like a top.  But when they stop the ride you don't go flying out.  That's because the wall holds you in and your move with the ride.  Well gravity acts like the wall and you move with the earth.\n\nYou would go flying of the earth if it continued to rotate and the gravity field somehow disappeared.
608387
The Earth's center contains a lot of molten iron; due to Earth's rotation, it rotates too, thus generating a magnetic field. It's bit more complicated, but in a nut that's the explanation.
112224
because it changes slowly, and also you don't feel the magnets on your frigde why would you feel the earth? :P
203243
Any magnetic field motion against any resistance will generate heat- It is a linear relationship, so the faster it moves, the greater heat generated.  There is no minimum speed below which NO heat is generated.
1134399
Not a this point in our evolution......we do not have the technology to build something that will protect us from the hot temperatures\nof the inner earth.  Your question is puzzeling, am not sure what \nyou have in mind.