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Magnetism is the force exerted by magnets once they attract or repel every other. Magnetism is caused by the activity of electrical charges.Every substance is made up of small units referred to as atoms. Each atom has actually electrons, corpuscle that carry electric charges. Spinning choose tops, the electrons circle the nucleus, or core, of one atom. Their movement generates an electrical current and causes each electron come act prefer a microscope magnet.

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In many substances, equal numbers of electron spin in the opposite directions, i beg your pardon cancels the end their magnetism. The is why products such as cloth or file are said to it is in weakly magnetic. In building material such together iron, cobalt, and also nickel, most of the electrons spin in the very same direction. This renders the atoms in these substances strong magnetic—but they space not however magnets.To come to be magnetized, one more strongly magnetic problem must enter the magnetic field of an currently magnet. The magnetic field is the area approximately a magnet that has actually magnetic force. Every magnets have actually north and south poles. The opposite poles space attracted to each other, when the very same poles repel every other. When you obstacle a item of iron follow me a magnet, the north-seeking poles of the atom in the iron line up in the exact same direction. The force generated by the aligned atom creates a magnetic field. The item of iron has come to be a magnet.Some substances have the right to be magnetized by an electrical current. When electrical energy runs v a coil the wire, that produces a magnetic field. The field approximately the coil will certainly disappear, however, as quickly as the electric present is turn off. Geomagnetic Poles

The earth is a magnet. Scientists execute not completely understand why, but they think the movement of molten steel in the Earth’s outer core generates electric currents. The currents create a magnetic field with invisible present of force flowing between the Earth’s magnetic poles. The geomagnetic poles room not the same as the North and also South Poles. Earth’s magnetic poles frequently move, due to task far beneath the Earth’s surface. The shifting locations of the geomagnetic poles are recorded in rocks that form when molten material called magma wells up with the Earth’s crust and pours out as lava. As lava cools and becomes hard rock, strongly magnetic particles in ~ the rock end up being magnetized by the Earth’s magnetic field. The particles heat up follow me the lines of force in the Earth’s field. In this way, rocks lock in a document of the position of the Earth’s geomagnetic poles at the time.

Strangely, the magnetic records of rocks formed at the same time it seems ~ to suggest to various locations because that the poles. Follow to the theory of bowl tectonics, the rocky key that make up the Earth’s difficult shell space constantly moving. Thus, the plates on i m sorry the rocks solidified have moved due to the fact that the rocks videotaped the position of the geomagnetic poles. These magnetic records also show that the geomagnetic poles have reversed—changed into the opposite type of pole—hundreds the times due to the fact that the planet formed.Earth’s magnetic ar does not move quickly or turning back often. Therefore, it have the right to be a beneficial tool for helping people find their means around. For numerous years, human being have provided magnetic compasses to navigate using Earth’s magnetic field. The magnetic needle that a compass lines up through Earth’s magnetic poles. The north finish of a magnet points toward the magnetic north pole. Earth’s magnetic ar dominates a region called the magnetosphere, which wraps roughly the planet and its atmosphere. Solar wind, charged particles native the sun, presses the magnetosphere versus the earth on the side facing the sun and also stretches it into a teardrop shape on the zero side. The magnetosphere protects the earth from many of the particles, yet some leak through it and also become trapped. When particles indigenous the solar wind hit atoms of gas in the upper atmosphere roughly the geomagnetic poles, they develop light displays called auroras. This auroras appear over places like Alaska, Canada and Scandinavia, wherein they are sometimes dubbed “Northern Lights.” The “Southern Lights” have the right to be viewed in Antarctica and brand-new Zealand.


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The steel in the sand is magnetic, strong attracted to the magnet ~ above an atom level.

Photograph by MaryLou Naccarato, MyShot


Historic DirectionsThe ancient Greeks and Chinese knew around naturally magnetic stones dubbed "lodestones." these chunks of iron-rich mineral may have been magnetized by lightning. The Chinese found that they might make a needle magnetic by stroking it versus a lodestone, and that the needle would suggest north-south.

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Animal MagnetismSome animals, such together pigeons, bees, and also salmon, can detect the Earth"s magnetic field and also use it come navigate. Scientists aren"t sure just how they perform this, but these creatures it seems to be ~ to have actually magnetic product in your bodies the acts choose a compass.