EARTH SCIENCE
MAGNETISM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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keeps its magnetism for a long time.
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cannot be destroyed by heat.
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easily loses its magnetism.
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began as molten rock on the ocean floor.
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Detailed explanation-1: -Assertion :Substances which at room temperature retain their ferromagnetic property for a long period of time are called permanent magnets. Reason: Permanent magnet can be made by placing a ferromagnetic rod in a solenoid and passing current through it.
Detailed explanation-2: -A permanent magnet is a magnet that keeps its magnetism for a long time. Permanent magnets are magnets that retain their magnetic properties even after the source of the magnetism is gone. Steel magnets, which are an iron-carbon alloy, are permanent magnets.
Detailed explanation-3: -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.