EARTH SCIENCE
MAGNETISM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A permanent magnet has a north pole and a south pole, but an electromagnet only has a south pole.
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A permanent magnet has a fixed magnetic field strength but the magnetic field strength of an electromagnet can be changed.
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A permanent magnet requires an external source of energy, but an electromagnet produces its own energy.
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The magnetic field lines from a permanent magnet emerge from the north pole, but they emerge from the south pole of the electromagnet.
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Detailed explanation-1: -The strength of Permanent Magnet depends on the material used for its creation, on the other hand, the strength of Electromagnet varies according to the flow of electric current into it.
Detailed explanation-2: -A permanent magnet is an object made of a material that gets magnetized and creates its own persistent magnetic field. An electromagnet is made from a coil of wire that acts as a magnet when an electric current is allowed to pass through it.
Detailed explanation-3: -Electromagnets have the main benefit of manipulating their magnetic pull strength – both by turning the magnet on or off and by adjusting the current. They also feature greater pull strength than permanent magnets.
Detailed explanation-4: -An electromagnet is made by winding copper wire around a soft iron core and passing current through that wire. It behaves as a magnet as long as current is flowing through the wire. Hence an electromagnet is a temporary magnet. It is not a permanent magnet.
Detailed explanation-5: -A permanent magnet is a naturally occurring magnet. However it is not strong enough and occurs in any shape. Thus a strong permanent magnet is made of steel by passing current through an insulated coil wound over it. It produces a permanent magnetic field and polarity that cannot be altered.