EARTH SCIENCE
MAGNETISM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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by rubbing it with a stronger magnet
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by increasing the coils of wire around the iron
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by increasing the length of the wire from the battery
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by loosening the coil of wire around the iron
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Detailed explanation-1: -Electromagnet is a soft iron core made into a magnet by passing electric current through a coil surrounding it. There are two methods by which we can increase strength of magnetic field are: 1) By increasing the number of turns of wire in the coil. 2) By increasing the current flowing the coil.
Detailed explanation-2: -The greater the current, the greater the strength. This because the current increases there is more flow of electrons which in turn increases the magnetic field around it. (b) The number of turns is increased. The greater the number of coils, the greater the strength.
Detailed explanation-3: -Electricity and magnetism are linked phenomena. The more loops the coil has, the stronger the magnetic field, while the current is flowing.
Detailed explanation-4: -We can say that, the strength of the electromagnet is directly proportional to the number of turns in the coil. If you double the number of turns, you double the strength of the electromagnet.
Detailed explanation-5: -As the soft iron core is a highly ferromagnetic material, It allows (and attracts) the magnetic field lines to pass through it. When such material is used in the electromagnet, the magnetic field lines passing through it increases, thereby, the strength of the electromagnet increases.