EARTH SCIENCE
MAGNETISM
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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true
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false
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Either A or B
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None of the above
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Detailed explanation-1: -False. Hint: Earth has two geographic poles, North pole and South pole. Also earth has two magnetic poles of North and South.
Detailed explanation-2: -But some magnets have more than two poles. In fact, some have four, or six, or even eight!
Detailed explanation-3: -Anyway, the earth has two dominant magnetic poles, and several very weak ‘quadrupolar’ poles of which there are, at least mathematically, about 8 in number. These poles are far weaker than the dipole field, and measure only weak departures of the local geographic field strength from the basic dipolar North-South field.
Detailed explanation-4: -Solution: (i) False; A magnet of any shape always has two poles: a north pole and south pole.
Detailed explanation-5: -At Earth’s surface, the magnetic field forms two poles (a dipole). The north and south magnetic poles have opposite positive and negative polarities, like a bar magnet.