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
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easily loses its magnetism
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has two north poles
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Detailed explanation-1: -Temporary magnets are made of soft metals that are magnetised only when exposed to a permanent magnetic field or an electric current. When they come into contact with a magnetic field, they become magnetized . When the magnetic field is removed, they gradually lose their magnetism.
Detailed explanation-2: -A temporary magnet is a magnet made of soft iron, that is usually easy to magnetize; however, temporary magnets lose most of their magnetic properties when the magnetizing cause is discontinued.
Detailed explanation-3: -A temporary magnet can lose its magnetization in less than 1 hour. Neodymium magnets lose less than 1% of their strength over 10 years. Permanent magnets such as sintered Nd-Fe-B magnets remain magnetized indefinitely. Iron magnets need a keeper to complete the circuit and preserve the magnetism.
Detailed explanation-4: -Magnets lose their properties if they are heated, hammered or dropped from some height.