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The charged currents in the outer conduc...

The charged currents in the outer conducting regions of the earth's core are thought to be responsible for earth's magnetism. What might be the 'battery' (i.e., the source of energy) to sustain these currents ?

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One possibility can be the presence of radioactive elements in the interior of the Earth. But the actual cause is not understood well yet.
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The graph given here represents an idealized sinusoidal current flow between a cloud at a height of 1 km and the earth, during a lightning discharge. Value of I_(0) is 157 kA and T = 0.2 ms. Assume that discharge happens when the electric field in the air between the cloud and the earth becomes equal to the breakdown field of air i.e., E_(0) = 3 xx 10^(6) V//m (a) Calculate the total charge flow due to lightning. (b) Calculate the average current between the cloud and the earth during the lightning. (c) Assume that the entire charge on the cloud is released during the lightning and estimate the capacitance of the cloud – Earth system.

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MODERN PUBLICATION-MAGNETISM AND MATTER-NCERT FILE (NCERT TEXTBOOK EXERCISE)
  1. Answer the following questions: (a) The earth's magnetic field varies ...

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  2. The earth's core is known to contain iron. Yet geologists do not rega...

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  3. The charged currents in the outer conducting regions of the earth's co...

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    |

  4. The earth may have been reversed the direction of its field several ti...

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    |

  5. The earth's field departs from its dipole shpae substantially at large...

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  6. Answer the following questions: (a) The earth's magnetic field varies ...

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  7. A short bar magnet placed with its axis at 30^@ with a uniform extern...

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  8. A short bar magnet of moment 0*32JT^-1 is placed in a uniform external...

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  9. A closely wound solenoid of 800 turns and area of cross section 2*5xx1...

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  10. If the solenoid in the above question is free to turn about the vertic...

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  11. A bar magnet of magnetic moment 1.5JT^-1 lies aligned with the directi...

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  12. A closely wound solenoid of 2000 turns and area of cross section 1.6xx...

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  13. A circular coil of 16 turns and radius 10cm carrying a current of 0.75...

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  14. A magnetic needle free to rotate in a vertical plane parallel to the m...

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  15. At a certain location in Africa, a compass points 12^(@) west of the g...

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  16. A short bar magnet has a magnetic moment of 0*48JT^-1. Give the direct...

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  17. A short bar magnet placed in a horizontal plane has its axis aligned a...

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  18. If the bar magnet in the above problem is turned around by 180^@, wher...

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  19. A short bar magnet of mangetic moment 5*25xx10^-2JT^-1 is placed with ...

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  20. Why does a paramagnetic sample display greater magnetisation (for the ...

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