EARTH SCIENCE
MAGNETISM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A magnet made of material that always keeps its magnetism
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A temporary magnet that gives off a magnetic force for a period of time.
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Those which are found in nature, like magnetite
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None of the above
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Detailed explanation-1: -A permanent magnet is an object made from material that can be magnetized and creates its own persistent magnetic field. These materials are strongly attracted to magnets. These are made up of iron, nickel, cobalt, steel and some alloys of rare-earth metals.
Detailed explanation-2: -A permanent magnet is an object made from a material that is magnetized and creates its own persistent magnetic field. As the name suggests, a permanent magnet is ‘permanent’. This means that it always has a magnetic field and will display a magnetic behavior at all times.
Detailed explanation-3: -A magnet made from a material that keeps its magnetism for a long time is called a permanent magnet.
Detailed explanation-4: -In permanent magnets, a property called coercivity is present, which means they can withstand being demagnetized without becoming weak. Materials such as Sm-Co and Nd-Fe-B have high coercivities, in contrast to older materials like Alnico or ceramic materials [hard ferrite].
Detailed explanation-5: -Magnets can be made by placing a magnetic material, such as iron or steel, in a strong magnetic field. Permanent, temporary, and electromagnets can be produced in this manner.