The earth may have been reversed the dir...

The earth may have been reversed the direction of its field several times during its history of 4 to 5 billion years. How can geologists know about the earth's field in such distant past ?

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During solidification of rocks, the pattern of Earth.s magnetic field got weakly recorded in them. When these rocks are analysed for their magnetism, they give us clues regarding the magnetic history of the Earth

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A : In earn may nave even reversea the direction of its field several time during its history of 4 to 5 billion years. R: Earth's magnetic field gets weakly' recorded' in certain rocks during solidification.

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MODERN PUBLICATION-MAGNETISM AND MATTER-NCERT FILE (NCERT TEXTBOOK EXERCISE)

Answer the following questions: (a) The earth's magnetic field varies ...
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The earth's core is known to contain iron. Yet geologists do not rega...
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The charged currents in the outer conducting regions of the earth's co...
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The earth may have been reversed the direction of its field several ti...
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The earth's field departs from its dipole shpae substantially at large...
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Answer the following questions: (a) The earth's magnetic field varies ...
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A short bar magnet placed with its axis at 30^@ with a uniform extern...
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A short bar magnet of moment 0*32JT^-1 is placed in a uniform external...
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A closely wound solenoid of 800 turns and area of cross section 2*5xx1...
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If the solenoid in the above question is free to turn about the vertic...
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A bar magnet of magnetic moment 1.5JT^-1 lies aligned with the directi...
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A closely wound solenoid of 2000 turns and area of cross section 1.6xx...
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A circular coil of 16 turns and radius 10cm carrying a current of 0.75...
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A magnetic needle free to rotate in a vertical plane parallel to the m...
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At a certain location in Africa, a compass points 12^(@) west of the g...
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A short bar magnet has a magnetic moment of 0*48JT^-1. Give the direct...
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A short bar magnet placed in a horizontal plane has its axis aligned a...
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If the bar magnet in the above problem is turned around by 180^@, wher...
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A short bar magnet of mangetic moment 5*25xx10^-2JT^-1 is placed with ...
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Why does a paramagnetic sample display greater magnetisation (for the ...
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